Supplemental Lecture: Human capital in developing countries — Transcript
Full transcript
- 0:02when we get started here
- 0:05um thank you for coming um
- 0:08to this third lecture uh first lecture
- 0:11on thursday the first supplemental
- 0:13lecture
- 0:14of the class um my name is joe kobaski
- 0:18i'm uh one of the co-leaders with doug
- 0:20golin of the steg program
- 0:22this course is being offered
- 0:26by organized through the steg program
- 0:28which is supported by the united
- 0:30kingdom's foreign commonwealth and
- 0:31development office
- 0:33as part of the uk effort
- 0:37we have people in the front row as
- 0:39panelists
- 0:41you can interrupt use the microphone we
- 0:43encourage you to interrupt with
- 0:45questions
- 0:45just as in a normal classroom but
- 0:48otherwise if you're not interrupting
- 0:49please mute yourselves
- 0:52those of you who are viewing as a
- 0:54webinar you can address questions in the
- 0:56q
- 0:57a you can upvote them we'll be trying to
- 1:00um answer those as we can
- 1:04and if there's you know particular
- 1:05popular questions uh
- 1:07um todd shulman will um leave some time
- 1:12at the end
- 1:13to answer the questions uh the lecture
- 1:16notes
- 1:16are posted at the stag website uh there
- 1:19will be a youtube recording this is also
- 1:21being broadcast
- 1:22via youtube so you can go back and watch
- 1:24it on youtube i want to thank todd
- 1:26schulman from the minneapolis fed for
- 1:29teaching the class today
- 1:31again he's doing this out of the
- 1:32kindness of his heart i want to thank
- 1:34mandy and kirsty from cepr for
- 1:39everything that they've done
- 1:40for logistics and um i want to announce
- 1:43that
- 1:44tomorrow we have uh bertolt herrendorf
- 1:47who will be talking about structural
- 1:48transformation at the same time
- 1:514 p.m london time um okay todd go ahead
- 1:56all right thanks i want to say first
- 1:58thanks
- 2:00to both of you for organizing this whole
- 2:02enterprise and and
- 2:03these lectures in particular and for
- 2:06inviting me today so what i'm supposed
- 2:08to talk about is
- 2:09human capital in developing countries
- 2:12since i work for the fed i have to stop
- 2:13and make sure you all see here that
- 2:15these are my views about human capital
- 2:16in developing countries and not the
- 2:18federal reserve banks
- 2:22so i like to start by just making sure
- 2:24we're on the same page i think we often
- 2:26talk about human capital but here's
- 2:27going to be my formal definition of it
- 2:29i want to think about it as being the
- 2:31stock of productivity enhancing
- 2:33attributes embedded in people
- 2:35and for clarity i want to make sort of
- 2:37two points right up front
- 2:39the first is that in general we should
- 2:40think about this as being a vector as
- 2:42being a multi-dimensional stock it
- 2:44includes a wide variety of attributes
- 2:46it includes the knowledge of workers
- 2:48their skills the habits they develop
- 2:50over the course of their life their
- 2:52health
- 2:52which helps them be more productive on
- 2:54the job so i want to think about this as
- 2:56being a long vector of attributes that
- 2:58people have
- 2:59the second kind of key attribute
- 3:02component of human capital is that it's
- 3:03generally produced through investments
- 3:06okay so there's some active uh
- 3:09expenditure of time or resource that
- 3:10goes into enhancing human capital
- 3:13for example education is used to produce
- 3:16knowledge
- 3:16training or practice to produce skills
- 3:18and habits exercise to improve your
- 3:20health etc etc etc
- 3:23i think it's really common when we talk
- 3:24about human capital to jumble all of
- 3:26this stuff together
- 3:28primarily to be honest for measurement
- 3:30reasons we can't really
- 3:32measure human capital and often we can't
- 3:34really measure your knowledge or your
- 3:36skills exactly
- 3:37what we find it easiest to measure is
- 3:39how long you spent sitting in classrooms
- 3:41how many years you went to school
- 3:43maybe we can measure how many minutes a
- 3:45day you exercise even if we can't
- 3:46measure your health
- 3:47but at least at the outset i want you to
- 3:49kind of be clear these are distinct
- 3:50objects
- 3:52human capital has a long history in
- 3:54economics although it wasn't always
- 3:55referred to by that name if you go
- 3:57all the way back to adam smith you'll
- 3:58see he talks about the skills of workers
- 4:00and how
- 4:01workers with different skill levels have
- 4:02different productivities
- 4:04that's the same idea but it was really
- 4:06brought to the forefront of economics in
- 4:08the late 50s and early 1960s when
- 4:11becker minster and others started to
- 4:13work out a full theory of human capital
- 4:16what i mean by a full theory of it is
- 4:17that they have a models
- 4:19where workers or their families are
- 4:22making investments and they have
- 4:24rational cost benefit type
- 4:25considerations you know how long should
- 4:27i go to school
- 4:28i should go until the return on going to
- 4:30school is equal to the return on other
- 4:32activities i might undertake
- 4:33things like that okay from that time
- 4:36there's been a huge explosion in the
- 4:38literature
- 4:38and there's you know a great deal of
- 4:40work on human capital
- 4:42in general what i want to do today
- 4:46since there's been so much work because
- 4:47i'm going to focus on two very
- 4:49specific things that i think fit well
- 4:51with the theme of macro development and
- 4:53stag and
- 4:54that you're working through the first
- 4:57thing i want to do is measure
- 4:59as best we can or really estimate might
- 5:01be a better word
- 5:02cross-country differences in the stock
- 5:03of human capital
- 5:05when i do that i'm going to try to
- 5:06convince you of two things i think
- 5:08there's sort of
- 5:09two emerging uh there is an emerging
- 5:11consensus here which is that
- 5:13cross-country differences and human
- 5:14capital stocks are large
- 5:17that's a statement that has to be
- 5:18relative to something and i'm going to
- 5:20think of it as
- 5:20human capital stocks or large
- 5:22differences in human capital
- 5:24stocks are larger than what the early
- 5:27consensus held
- 5:28the early consensus would be like what
- 5:30julieta taught last week
- 5:31and i'll try to be more precise about
- 5:33that in a minute
- 5:35the second is i'm going to say that it's
- 5:36large relative to cross-country income
- 5:38differences
- 5:39that is to say that human capital plays
- 5:41an important role
- 5:42in thinking about why rich countries are
- 5:44much richer than poor ones
- 5:46there's relatively less evidence on
- 5:50the role that it plays for example in
- 5:52structural transformation
- 5:53i know that's a key theme of stag so
- 5:55i'll try to highlight a few references
- 5:56and
- 5:57some of the work that's being done in
- 5:58that area but i think that's an area
- 6:00that we need a lot more work on
- 6:03since i'm going to be focusing on these
- 6:04cross-country issues
- 6:06in other words comparing human capital
- 6:08stocks between rich and poor countries
- 6:10or middle income and poor countries
- 6:12i'm going to have relatively less to say
- 6:14on the vast and excellent literature on
- 6:16within country human capital differences
- 6:18that's just a function of how much time
- 6:19we have today i don't have time to get
- 6:21into it
- 6:22do you take as given that um there are
- 6:25large differences in human capital
- 6:26stocks
- 6:27across countries or across sectors
- 6:29within a country
- 6:30then as somebody who works on macro
- 6:32development or who's interested in
- 6:33structural transformation you might want
- 6:35to build human capital into your
- 6:36thinking and
- 6:37one way that we we of course make
- 6:39progress here is by building models
- 6:41and so i'm going to try to give you some
- 6:42ideas the second thing i want to do is
- 6:44illustrate the key model mechanisms that
- 6:46you can use to think about human capital
- 6:48differences across sectors and across
- 6:49countries
- 6:51so i'm going to build on some very
- 6:52classic results especially from becker
- 6:54and ben parath i'm going to show you
- 6:56three maybe four if i have enough time
- 6:57of the main mechanisms that people use
- 6:59to generate human capital differences
- 7:02as the results of workers and their
- 7:04families endogenously deciding how much
- 7:06human capital to acquire that's kind of
- 7:08the
- 7:08underlying idea
- 7:13i think it's always useful to at the
- 7:15outset say sort of what's the underlying
- 7:17challenge that we confront
- 7:19and with human capital i think it's
- 7:20really a big one and i like to pose it
- 7:23as a simple thought experiment which is
- 7:25imagine i ask you
- 7:26even pick within a country take two
- 7:29workers
- 7:30imagine i ask you to explain why some of
- 7:32those workers are more productive than
- 7:33others what drives productivity
- 7:34differences between workers
- 7:37even if you focus on a country like i'm
- 7:39an american i live in the united states
- 7:41you know why are some americans more
- 7:43productive than others
- 7:45i'm hard-pressed to tell you and i don't
- 7:47think the economic literature has
- 7:48settled on an answer how much of that is
- 7:50human capital
- 7:51versus how much of its other
- 7:52characteristics like luck or the job you
- 7:55type
- 7:56you happen to work in or how much of
- 7:57it's driven by things like
- 7:58discrimination
- 7:59you know those are questions that people
- 8:01are wrestling with
- 8:03now in other literatures and i don't
- 8:05think they're settled issues
- 8:07even if we agree that it's human capital
- 8:09i think we're also going to have a hard
- 8:10time putting our finger on exactly what
- 8:12it is
- 8:13and an easy way i can say this to you is
- 8:15that i have the good fortune to work
- 8:17with ed prescott
- 8:19ed is like me a phd educated economist
- 8:23so we have the same job we have the same
- 8:25employer
- 8:26we have the same education level and yet
- 8:29ed is vastly more productive than i am
- 8:31at producing economics papers why is
- 8:34that i think we can all agree it's
- 8:35something that ed has it's some human
- 8:37capital characteristics that he has that
- 8:38i don't have but if i ask you to put
- 8:41your finger on exactly what those are
- 8:42to measure them you would have a hard
- 8:44time doing that
- 8:46what we're going to do today is
- 8:47something that's even tougher than that
- 8:49we're going to try to investigate these
- 8:50differences across countries
- 8:52the set of relevant human capital
- 8:54characteristics that we might be
- 8:55interested in is going to be even larger
- 8:58and the set of confounding or
- 8:59environmental factors that we need to
- 9:00think about and control for is even
- 9:02larger
- 9:03and so in general i want you to just
- 9:05acknowledge right up front
- 9:06measuring cross-country differences in
- 9:08human capital stocks is really tough
- 9:11i'm going to give you my best guess you
- 9:12know the best approaches that i think
- 9:13we've discovered so far i'm going to
- 9:15give you the answers that they lead to
- 9:17but i want you to be throughout this
- 9:19vaguely dissatisfied
- 9:20because i think a vague and persistent
- 9:22sense of dissatisfaction
- 9:24is a great tool for research you know if
- 9:25you're never quite happy with what's
- 9:27been done
- 9:27and you're always a little uncomfortable
- 9:29with the assumptions that's a great way
- 9:31to get started in your own work
- 9:33all right so let's start with part one
- 9:35how do we measure human capital
- 9:36differences
- 9:41the techniques i'm going to show you two
- 9:43different ways to go about doing this
- 9:44and they're both going to be closely
- 9:46tied to development accounting
- 9:48so just like julieta's lecture last
- 9:50friday so she's done a great
- 9:51introduction to this
- 9:53i'm just going to remind you a little
- 9:54bit of the basics that i need and then
- 9:56we'll get going
- 9:58so for development accounting what you
- 10:00really need the main assumption you
- 10:01start with is about the aggregate
- 10:03production function
- 10:04so i'm going to think about capital y
- 10:06that's output
- 10:07that's ppp adjusted gdp of country c
- 10:11as being a cobb douglas production
- 10:13function of the physical capital
- 10:15measured in ppp adjusted dollars raised
- 10:19to the capital share
- 10:20and then tfp total factor productivity
- 10:24and the total human capital stock of
- 10:25country c
- 10:27okay and julieta walked you through last
- 10:29time we think that we have good evidence
- 10:31that this production function
- 10:32provides a useful fit to the data we
- 10:34think we roughly know what these
- 10:36factor shares the alphas are so this is
- 10:38sort of a good starting point for us
- 10:41just like she did i'm going to divide
- 10:43both sides through by the stock of
- 10:45workers in the country
- 10:46so then i can think about gdp per worker
- 10:48in country c
- 10:50and that's going to be determined by
- 10:51three components that she talked about
- 10:53the capital to output ratio raised to a
- 10:55power
- 10:57total factor productivity and the human
- 10:59capital stock per worker
- 11:01people will sometimes call this last
- 11:03piece the average human capital you do
- 11:05actually technically need extra
- 11:06assumptions to say that
- 11:07i may slip and call it that myself but
- 11:09anyway human capital per worker
- 11:13so generically in the development
- 11:15accounting literature what we're trying
- 11:16to do is
- 11:17understand differences or variation in
- 11:19this gdp per worker as a function of
- 11:22how much capital to output every country
- 11:23has the tfp in every country
- 11:26and the human capital per work in every
- 11:28country
- 11:29today i'm going to be really focused on
- 11:31what can we say about human capital
- 11:33so i'm going to lump the rest of it
- 11:35together and just call it z
- 11:37other stuff that i'm not interested i'm
- 11:38not going to try to measure i have
- 11:39nothing to add there
- 11:41and so we're just going to ask what can
- 11:43we say about human capital
- 11:47like julieta did i'm going to take logs
- 11:48of this equation so basically we're
- 11:50going to investigate
- 11:51variation or differences in log gdp ppp
- 11:54adjusted gdp per worker
- 11:56that's pen world tables 10.0 that's
- 11:59going to be in part a function of
- 12:00capital output and tfp differences
- 12:03and part human capital per worker
- 12:05differences
- 12:06okay so that's just to get you back to
- 12:08where julieta left us and what we're
- 12:09going to do now is consider what what is
- 12:11sort of the
- 12:12the best evidence about how we can
- 12:14measure this object h
- 12:16and think about its contribution to the
- 12:18ppp gdp per worker difference as we see
- 12:23i've already established that that's a
- 12:24challenge and and julieta did a nice job
- 12:26with this but
- 12:27i do want to take one extra minute and
- 12:28point out that regressions are probably
- 12:30not going to be the way that we
- 12:32identify or measure h or its importance
- 12:34for cross-country income differences
- 12:37she gave you one perspective on this
- 12:38which is that you should think about
- 12:39this as being a production function and
- 12:41the estimation of production functions
- 12:43is a very difficult task
- 12:46another way to think about this is that
- 12:48i like to borrow from
- 12:50mancus bookings papers
- 12:53he has a very nice discussion of the
- 12:55problems with cross-country regressions
- 12:57and his view is that this is really a
- 12:59very simple and practical problem
- 13:02at the end of the day if i want to
- 13:03investigate human capital using
- 13:05cross-country
- 13:06regressions how many countries do i have
- 13:08something like a hundred
- 13:09is typically how many countries you're
- 13:10going to be able to get data for
- 13:12and if i want to think about
- 13:13cross-country differences you know how
- 13:15many right hand side variables would i
- 13:17want to include how many things do i
- 13:18think might generate cross-country
- 13:20income differences including human
- 13:21capital
- 13:22skills capital institutions etc etc
- 13:26and his point that he makes very nicely
- 13:28is just that if you only have 100
- 13:29observations and you have hundreds of
- 13:32things you might think about as being
- 13:33determinants of
- 13:34gdp per worker it's kind of a hopeless
- 13:36endeavor
- 13:38and so we need to find a way to
- 13:39circumvent this we need to find a way so
- 13:41that we can have more than just 100
- 13:42observations to help us learn about
- 13:45human capital so how are we going to do
- 13:48that
- 13:52sorry 10 a.m here so i still need coffee
- 13:55um we're going to build on two
- 13:57assumptions that are going to allow us
- 13:59to make substantial progress and this
- 14:01was first worked out by bills and clean
- 14:02out a 2000 aer paper
- 14:05those two assumptions i'll just state
- 14:07them first and then we'll talk a little
- 14:08bit about their significance
- 14:10the first is that there's perfect
- 14:11substitution among different labor types
- 14:14which is sometimes called the efficiency
- 14:15units assumption
- 14:17what this assumption means is that for
- 14:19the purposes of producing
- 14:20aggregate output we all supply
- 14:23labor there's only one input called
- 14:25labor
- 14:27some of us just happen to provide more
- 14:28or less than others
- 14:30so you know the way to think about this
- 14:32is okay if you
- 14:33add up enough todd shulman's eventually
- 14:35you can have a bill gates and we just
- 14:37have to figure out how many todd
- 14:38shulman's it takes
- 14:39to provide the labor input of the bill
- 14:41gates or whoever your famous
- 14:42your favorite famous person is but there
- 14:45exists some number and we know what that
- 14:46is we can solve it
- 14:48okay the second assumption is that labor
- 14:51markets are competitive
- 14:53and what that really means is that
- 14:55workers and firms take prices as given
- 14:57or that prices are set by marginal
- 14:58products
- 15:00okay under these two assumptions
- 15:03we can use the firm's first order
- 15:05conditions to characterize the demand
- 15:07for workers who have hi units of human
- 15:10capital in country c
- 15:12so the competitive labor markets
- 15:13assumption we're going to use that first
- 15:15to say that the wage of worker i in
- 15:17country c is equal to their marginal
- 15:19product of their labor
- 15:22then we're going to take the derivative
- 15:24we're going to just find what that
- 15:25marginal
- 15:26product is and it's going to depend on
- 15:27the labor share the capital output ratio
- 15:30tfp and the human capital of the worker
- 15:33and here's where the perfect
- 15:35substitution assumption shows up
- 15:37it says that the marginal product of
- 15:39labor depends on how many units of human
- 15:41capital they provide
- 15:43in a world where there's not perfect
- 15:45substitution but there's different types
- 15:46of labor there's an
- 15:47extra term that shows up here which is
- 15:49the price of my type of labor
- 15:51so for example if you're used to
- 15:53thinking about models where there's
- 15:54skilled and unskilled labor and they're
- 15:56different inputs maybe with a ces
- 15:57production function
- 15:59then you would have a term here that
- 16:00says what's the price of skilled or
- 16:02unskilled labor
- 16:04the fact that we don't have that comes
- 16:05from the perfect substitution assumption
- 16:08so that's what those two assumptions buy
- 16:10us
- 16:11if you stare closely at this equation
- 16:13you'll see that there's the capital
- 16:14output
- 16:15in t of p terms just like before that's
- 16:16what i labeled z
- 16:18on the last slide so we've got that same
- 16:19z that's what this really tells us is
- 16:22that the wage of worker i in country c
- 16:24depends on that country stuff
- 16:26and the workers human capital
- 16:30i find it most useful to explain
- 16:34the power of these assumptions by
- 16:35turning this whole thing around
- 16:39what this says is that if a worker has
- 16:42twice as much human capital they're
- 16:43going to make twice as
- 16:44twice as high of a wage but in practice
- 16:47what we really want to do is
- 16:48invert that and use it the other way
- 16:50around we want to say if i see a worker
- 16:53making twice as high wages they must
- 16:55have twice the human capital
- 16:58and the reason that's really useful is
- 17:00on the last slide i was saying boy if we
- 17:02want to measure human capital using
- 17:03cross-country evidence we only have 100
- 17:05or so countries maybe 200 at the most
- 17:08here i'm saying well if i see a worker
- 17:10with twice as high of wages i know they
- 17:12have twice the human capital
- 17:14now i'm using evidence on workers wages
- 17:16how many observations do i have on the
- 17:18wages of workers
- 17:20billions at this point it really is
- 17:22billions of observations
- 17:23and so this is going to give me a lot
- 17:25more evidence it's going to allow me to
- 17:26draw on a lot more data
- 17:28to discipline the measurement of human
- 17:30capital
- 17:32and now you can really think about okay
- 17:33so what i need what i want to be able to
- 17:35do i said
- 17:37is i want to be able to say if i see a
- 17:38worker who has twice as high of wages
- 17:41he must have twice the human capital now
- 17:44you can really see what those
- 17:45assumptions are doing for me
- 17:47if there was imperfect substitution
- 17:48across labor types that inference no
- 17:50longer holds because i have to worry
- 17:52well maybe he's just a different type of
- 17:53worker and that type of worker has a
- 17:55different price
- 17:57if labor markets are not competitive
- 17:58then the fact that a worker makes twice
- 18:00the wage could just be due to
- 18:02discrimination or market power
- 18:05or luck or all sorts of other factors
- 18:08okay
- 18:09so that's what those assumptions bias
- 18:10they're both really important
- 18:11assumptions i'll come back and talk a
- 18:13little bit about them
- 18:14later on i don't have time to dig into
- 18:16the whole literature on these
- 18:17today but i think i want you to
- 18:19understand that's what they get us
- 18:21they allow us to take this from being a
- 18:23cross-country problem
- 18:24to a cross-worker problem and that's
- 18:26really what's unlocked the measurements
- 18:28of human capital
- 18:30sorry todd can i ask a question on this
- 18:32yes please
- 18:33so just irrespective of the two
- 18:35assumptions we are already
- 18:37we also make an assumption on kind of
- 18:39ruling out human capital externalities
- 18:41here right
- 18:42we are not as we are already assuming
- 18:44that h
- 18:46aggregate h doesn't have a direct effect
- 18:48on a right on on z
- 18:54yes there is a small literature that
- 18:57tries to measure those human capital
- 18:59externalities and i'm going to skip it
- 19:00today
- 19:01and and there's really it's a practical
- 19:03thing um
- 19:05it is extremely difficult to measure
- 19:07externalities
- 19:08if you think about what i'm doing here
- 19:10the underlying idea is that i'm saying
- 19:12uh i can learn about the productivity of
- 19:14a worker from looking at their wages and
- 19:15their marginal products
- 19:17and sort of the defining feature of
- 19:18externalities is of course that they're
- 19:20not priced in the market which makes
- 19:22them hard to measure through this
- 19:23approach
- 19:24so i can point you to the couple of
- 19:26papers that i think have made the best
- 19:27progress on that that is a
- 19:28much trickier issue and one that i'm not
- 19:30going to get into today
- 19:34thank you all right
- 19:38so suppose i take this equation very
- 19:40simple equation right and i just take it
- 19:42in logs
- 19:44then i have a very nice log linear wage
- 19:46equation which says that the log wage of
- 19:48worker i and country c
- 19:50is additive in two terms there's a part
- 19:54that depends on the country you live in
- 19:55that captures tfp and capital output
- 19:57ratios
- 19:59and there's a part that depends on your
- 20:00human capital
- 20:03what's really nice about this is if you
- 20:05lay it up next to
- 20:07okay let me do this differently there's
- 20:09a very nice connection here
- 20:11to the enormous labor literature in
- 20:14particular the micro labor literature
- 20:16that starts with jacob mintzer
- 20:17and his 1974 book in that book
- 20:21minser argues that log wages in the
- 20:24united states
- 20:26are approximately linear in schooling
- 20:28and quadratic in experience
- 20:30so he investigates a whole sets of
- 20:32different ways to model wages in the
- 20:34united states
- 20:35and he says the best way to model wages
- 20:37is to think about them as being
- 20:39the log wages linear and schooling
- 20:40quadratic in experience
- 20:42this was enormously influential so tons
- 20:44of people have estimated
- 20:46equations of this form which is now just
- 20:48called the mincer wage equation
- 20:50not just in the united states but in
- 20:52countries all over the world
- 20:54and so what's really another neat
- 20:56feature about these two assumptions is
- 20:58that they
- 20:59allow us to have a wage equation that
- 21:01looks very
- 21:02much like what people have been doing in
- 21:04micro labor for
- 21:0540 50 years so if you kind of stare at
- 21:08those there's a bunch of connections i
- 21:10want you to see
- 21:12if you estimate a wage equation of this
- 21:14type within a country
- 21:16you'll see that the intercept captures
- 21:19all of these country specific effects
- 21:24okay so that's the first piece of
- 21:25connection the second thing is that of
- 21:28course this huge labor literature that's
- 21:29been
- 21:30estimating this minster wage equation
- 21:31they're including things like schooling
- 21:33and experience on the job those
- 21:36sound like attributes of human capital
- 21:38those sound like things we want to
- 21:39include in our measure of human capital
- 21:41so
- 21:41they have been estimating exactly these
- 21:44types of
- 21:44ideas and what they're doing when they
- 21:48estimate them these coefficients beta 1
- 21:50beta 2 beta 3 they speak to the value
- 21:54of those things now the way somebody in
- 21:57the minster literature thinks about this
- 21:58is they tell you the wage value how much
- 22:00does it increase wages
- 22:02you know how much does a year of
- 22:03schooling increase my wages that's what
- 22:05beta 1 picks up
- 22:07but under the assumptions i've made
- 22:08those also tell me how much more
- 22:09productive a year of schooling makes me
- 22:13and so those connections says that now i
- 22:15can bring to bear all of the evidence
- 22:17from this minster wage
- 22:18literature not just in the united states
- 22:20but really around the world at this
- 22:22point
- 22:23to tell me what sorts of characteristics
- 22:26of human capital i might want to include
- 22:29and what are the value
- 22:30of those characteristics and in this
- 22:32specification
- 22:34is experience just measured in years of
- 22:36experience
- 22:37yeah i'll be more precise in a second
- 22:39what almost everyone ends up doing is
- 22:41something called potential experience
- 22:44which is the years since you graduated
- 22:46school
- 22:48and then you're going to do a quadratic
- 22:50people i mean the literature is built
- 22:51from that over the years but that's
- 22:53really going to be the the
- 22:54starting point for everything okay thank
- 22:57you
- 22:57um excuse me so um
- 23:00by looking at this equation i can
- 23:01imagine that this is going to have
- 23:04huge errors terms so
- 23:07i'm i'm wondering how well this um
- 23:11like human capital factors are actually
- 23:12going to explain the differences in
- 23:14wages
- 23:15i'm just saying like if these factors
- 23:17explain only 10 percent of the
- 23:18dispersion in wages maybe it's not
- 23:20i mean they might be contributing
- 23:22factors but they're not going to give us
- 23:23a good measure
- 23:24that's a great point it's not so much
- 23:27about the standard errors it's about the
- 23:28r squared in a typical application the r
- 23:32squared of this regression will be 20 to
- 23:3430
- 23:34meaning you explain about 20 to 30
- 23:36percent of the variation in log wages in
- 23:38the sample
- 23:41and you're exactly right now you have to
- 23:42think okay but then what
- 23:45one hypothesis is that there's non-human
- 23:48capital stuff going on that drives wage
- 23:50variation
- 23:51right block the employer you happen to
- 23:54meet with discrimination etc
- 23:57another is that maybe i'm doing a lousy
- 23:58job of measuring human capital
- 24:02and i don't know that we've ever figured
- 24:03out exactly what it is but those 20 to
- 24:0530 percent r squared's you know they are
- 24:07a bit worrying in that sense and i
- 24:08agree completely yeah
- 24:12okay so these really tight connections
- 24:14are going to lead us to the to the first
- 24:15approach to measuring human capital
- 24:17stocks which i'm going to call the
- 24:18constructive approach
- 24:20and i don't mean that as opposed to
- 24:21destructive but i mean it to point out
- 24:23that you were literally going to
- 24:24construct human capital piece by piece
- 24:26with this approach so what you're going
- 24:27to do
- 24:28it's just a simple four-step procedure
- 24:31you're going to select
- 24:32some dimension of human capital that
- 24:34you're going to try to measure so think
- 24:35about it is i'm going to select
- 24:36schooling
- 24:38i'm going to measure each nation's stock
- 24:41how much schooling does every country
- 24:43have
- 24:45then i have all of this evidence from
- 24:46the menstrual waves equations about the
- 24:48value of schooling
- 24:50so if i know how much schooling every
- 24:51country has and i know how valuable it
- 24:53is how much it raises productivity
- 24:55then i can use that to aggregate and
- 24:57find a measure of human capital
- 24:59from schooling and i can in theory do
- 25:01this for a whole variety of attributes
- 25:03and so that's what i want to build on
- 25:04first and show you first
- 25:06i like to show this one first because
- 25:07this is the way the literature actually
- 25:09developed
- 25:11and so it's a good way to kind of get a
- 25:12sense of the intellectual history of the
- 25:14measurements of human capital
- 25:17so the way this literature started is
- 25:19from
- 25:21measuring years of schooling and i think
- 25:24the reason is kind of hopefully obvious
- 25:26which is the years of school years of
- 25:28schooling is
- 25:29it's the most obvious it's the most
- 25:31visible it was the first thing that
- 25:33mincer put in the wage equations and
- 25:34talked about right it was right there
- 25:35from the beginning
- 25:37it's also one of the earliest things
- 25:38that we got data on
- 25:40and richard hit on this in his in his
- 25:42first lecture data availability and the
- 25:44growth
- 25:45of data availability has been a
- 25:46fundamental driving force for macro
- 25:48development research
- 25:50so human caps right years of schooling
- 25:52is one of the very first things we have
- 25:53because it turns out that many countries
- 25:56collect data on how many students or
- 25:58what share of young people are enrolled
- 26:00in school
- 26:02and knowing how many people enrolled in
- 26:03school if you just kind of add that up
- 26:05through a through a cumulative process
- 26:06you can figure out sort of the average
- 26:08years of schooling in the population
- 26:11barrow and lee are kind of the most
- 26:13well-known people for providing these
- 26:14estimates and so that's what i've
- 26:16plotted here on the left
- 26:17this is simply average years of
- 26:19schooling in the population age
- 26:2115 or above from their data plotted
- 26:23against gdp per worker
- 26:25measured in 2017 us dollars from pen
- 26:28world tables 10.
- 26:29both easy to get data sets online so
- 26:32what you can see is that there's
- 26:33enormous variation in years of schooling
- 26:35and this makes this a very likely and
- 26:37obvious culprit for including in our
- 26:39measures of human capital
- 26:41the richest countries in the world
- 26:43especially those that started getting
- 26:44educated early
- 26:45they have something like 13 to 14 years
- 26:47of schooling on average in their
- 26:49populations
- 26:50the poorest countries in the world that
- 26:52might be as low as two years of
- 26:53schooling
- 26:55okay people don't talk about it a lot
- 26:58but i think it is kind of interesting to
- 26:59look at the long run dynamics of this
- 27:01process and so
- 27:03uh lee and lee and one of these leads is
- 27:05the same as this lee
- 27:06built on the barrel and lead database
- 27:08but went back in time and measured
- 27:11or took the best possible estimates of
- 27:12enrollment as far back as you could go
- 27:16and they argued that it was possible to
- 27:17measure educational attainment from 1870
- 27:20onward for many countries so what i've
- 27:21shown you here is just sort of the
- 27:22long-run development of education which
- 27:24i like to do to give you a sense of the
- 27:26historical perspective
- 27:28so you can see for example that part of
- 27:30the reason why the united states is very
- 27:32educated today is that it's been
- 27:33educated for a long time
- 27:35way back in 1870 it was already the most
- 27:37educated country in the world
- 27:39you can see here japan has caught up
- 27:41fairly quickly it used to be relatively
- 27:43less educated and has grown quickly
- 27:46china is also becoming educated quickly
- 27:48the nice thing about china and one
- 27:50reason i want to show you this chart is
- 27:51that i want you to understand human
- 27:52capital is very slow moving
- 27:55because it's human capital of the
- 27:56workforce and so if you start investing
- 27:59a lot
- 28:00building you know secondary schools
- 28:02building colleges
- 28:03paying people to go to college you know
- 28:05making tuition free all of those
- 28:07policies
- 28:07you do that today
- 28:10you're going to affect the workforce but
- 28:12very slowly because the workforce
- 28:14includes some people who are 60 65 70
- 28:16years old
- 28:18and so your 60 65 70 year olds will not
- 28:20be highly educated for another 30 40
- 28:22years and that's sort of what's slowing
- 28:24china down they're investing a huge
- 28:25amount in education
- 28:26but it takes a long time for this to
- 28:28play out
- 28:30and then i've included down here a
- 28:31couple of sub-saharan african countries
- 28:33just to make the point that
- 28:34even within regions there's huge
- 28:36diversity of experiences so you can see
- 28:37here
- 28:38ghana has had phenomenal growth they're
- 28:42investing a ton in education and in fact
- 28:44they're up around china
- 28:45and brazil at this point whereas niger
- 28:48is lagging badly and is way behind
- 28:51okay so this is all to say that
- 28:54education i think is sort of the most
- 28:55obvious most visible it's something
- 28:57we've been investing in a lot for a long
- 28:59time this is the first thing we're going
- 29:00to want to include in our measure of
- 29:01human capital
- 29:04the second thing we need is an estimate
- 29:07of what's the value
- 29:09of education now right from the very
- 29:12beginning in the united states there was
- 29:14the literature argued that wages were
- 29:15about log linear in schooling
- 29:18if that's true then the value of
- 29:20schooling is just
- 29:21the slope it's just sort of what's beta
- 29:241 for my regression before what's the
- 29:25return to schooling as people in the
- 29:27micro literature often call it
- 29:30mincer argued from the very beginning
- 29:32that looked like something in the range
- 29:33of eight to ten percent
- 29:35was right for the united states that
- 29:38value seems to be fairly persistent over
- 29:40time we get
- 29:40fairly similar numbers now
- 29:44what's nice about this is that as i said
- 29:46people have run regressions of this type
- 29:47in many countries around the world and
- 29:49so people have been collecting what is
- 29:50the return to schooling for countries
- 29:52around the world
- 29:54and that's what's plotted here on the
- 29:56right this is the data from the most
- 29:58recent database
- 30:00i've tried to always include the source
- 30:01of the data and you can actually click
- 30:03all of these links if you have the
- 30:04slides open and it'll take you to the
- 30:05reference if you want to get any of this
- 30:08so this is a database that has collected
- 30:11these returns to schooling and i've just
- 30:13plotted what is the return against gdp
- 30:15per worker
- 30:17you can see that there's substantial
- 30:19variation right you see some countries
- 30:21where it seems like the estimated return
- 30:23is two three four percent you can see
- 30:24some countries where it's like twenty
- 30:26thirty percent
- 30:27what's maybe surprising but shows up
- 30:30persistently in studies that do this
- 30:33is that the return to schooling on
- 30:34average does not vary much between poor
- 30:36and rich countries
- 30:39sometimes you'll find it's a little
- 30:40higher in poor countries sometimes you
- 30:42find it's the same
- 30:43but not that different so i think what
- 30:46many people have done is take this as
- 30:48being evidence of saying that the return
- 30:49to schooling around the world
- 30:50a good estimate would be eight to ten
- 30:52percent okay
- 30:59so this leads us to the classic estimate
- 31:01of human capital i should have put some
- 31:02references here i'm sorry but this
- 31:04is what a classic estimate would be like
- 31:05holland jones 99 or caselli's handbook
- 31:08chapter from 2005.
- 31:11their estimates of human capital that
- 31:12you get these very traditional estimates
- 31:14are built on years of schooling and in
- 31:16particular they're built on the
- 31:18observation that there are large
- 31:19differences in years of schooling across
- 31:21countries
- 31:22and it seems like a year of schooling
- 31:23raises wages by eight to ten percent
- 31:26under those assumptions i described that
- 31:28would mean that a year of schooling
- 31:29makes a worker eight to ten percent more
- 31:31productive
- 31:33okay um here there's a bunch of
- 31:36references there's you know people have
- 31:37been building these databases on the
- 31:39returns to schooling so i've given you a
- 31:40bunch of different references that i
- 31:42think all end up pointing in the same
- 31:43direction
- 31:44poor and rich countries have similar
- 31:46returns maybe poor countries it's a
- 31:47little higher
- 31:50and that'll get us to a measure of human
- 31:51capital like what juliette gave on last
- 31:53friday
- 31:54which says that log wages and log human
- 31:56capital they're about
- 31:58linear in years of schooling so if i
- 32:00want to measure a country's
- 32:01human capital stock i'm going to say
- 32:04that the log of human capital is just 10
- 32:06times their average years of schooling
- 32:09and this is what people are in practice
- 32:11frequently doing
- 32:12okay if you do that just to give you
- 32:15some statistics for what i think is the
- 32:17classical measure of human capital
- 32:19you'll find that human capital in the
- 32:2190th percentile country divided by the
- 32:2310th percentile country that differs by
- 32:25about a factor of two
- 32:27whereas the total income difference is
- 32:28about a factor of 19 between those two
- 32:30countries
- 32:31okay so human capital that this is
- 32:33important you know i think we would all
- 32:35like to have
- 32:35twice as much human capital twice as
- 32:37much output that would be great
- 32:39but relative to the size of the thing
- 32:41we're trying to explain it's small
- 32:42and sort of that's you know here's the
- 32:44metric for that
- 32:45the 90 to 10 ratio of human capital
- 32:48divided by gdp worker that's like 11
- 32:50so we haven't explained that much and
- 32:51then people said well it seems like
- 32:52maybe human capital is not so important
- 32:56i prefer a little bit different
- 32:58development accounting metric
- 32:59everybody's got their favorite this is
- 33:00like one of these never-ending debates
- 33:03i kind of like to look at the covariance
- 33:04of log human capital log output divided
- 33:07by the variance of log output but
- 33:08it really doesn't matter what metric you
- 33:10use this gets you 19
- 33:12at the end of the day if this is your
- 33:13measure of human capital you're going to
- 33:14find it's not that important
- 33:19questions before i start showing you
- 33:20more components
- 33:25all right i have a i have a question may
- 33:27i ask yep
- 33:28please so i have a question about the
- 33:31years of schooling so is there any way
- 33:33that
- 33:33researchers include their the quality of
- 33:36schooling also
- 33:38give me two slides
- 33:43not for the basic thing but eventually
- 33:44people started to think about that
- 33:45that's the right answer
- 33:49all right so the second thing i want to
- 33:50include and juliette did put this into
- 33:52her measure of human capital on friday
- 33:54is
- 33:54experience think about this as right
- 33:57from the very beginning
- 33:59minser argued that experience was an
- 34:01important component of human capital
- 34:03more experienced workers have higher
- 34:05wages
- 34:06under the assumptions we've made that
- 34:07implies that more experienced workers
- 34:09are more productive
- 34:11up here i answered this question earlier
- 34:14i'm sorry i can't
- 34:15remember the names from flashing them in
- 34:16the screen but what is experience really
- 34:18almost always that means potential
- 34:20experience
- 34:22we would love to measure real experience
- 34:24like how many years or hours or months
- 34:26have you been working
- 34:28to do that really you need panel data i
- 34:31don't think anyone
- 34:32trusts the you know imagine asking you
- 34:34how many hours have you worked in your
- 34:35life for months or years
- 34:36you know the answer would be nonsense
- 34:38let's be honest i have no idea how many
- 34:40months or
- 34:40years i've worked in my life we wouldn't
- 34:43trust that answer
- 34:44and we don't have panel data for poor
- 34:46countries so instead of using actual
- 34:48experience what almost everybody does is
- 34:50they measure what we call potential
- 34:51experience that's how many years has it
- 34:52been since you graduated
- 34:54the idea is that's when you really
- 34:56started working you could have really
- 34:58started working after you finished your
- 34:59last degree
- 35:00all the time since then that's how much
- 35:02experience you could potentially have
- 35:04that's where the word potential comes
- 35:05from
- 35:07and then in practice that ends up being
- 35:09measured as something like age minus
- 35:10schooling minus six
- 35:13okay if you measure experience that way
- 35:15you're going to find that the level of
- 35:17experience is really similar in poor
- 35:19rich countries
- 35:22and the reason is actually very simple
- 35:23very intuitive
- 35:25poor countries you know you are
- 35:26developing countries have are younger
- 35:29they have very young populations they
- 35:31have young workforces and so they have
- 35:32lower ages on average among their
- 35:34workers
- 35:35but they go to school less so they have
- 35:37lower schooling
- 35:39if you construct experiences age minus
- 35:41schooling minus six
- 35:42what you're going to find is they have
- 35:43lower ages they have less schooling
- 35:46but the experience they have is almost
- 35:47exactly the same as what rich countries
- 35:48have on average
- 35:51okay so that's not what's going to be
- 35:53different
- 35:54it's not how much experience they have
- 35:56it's the value of that experience that
- 35:58we see in the labor market
- 36:00so what i'm plotting down here is the
- 36:02experience profiles for a select set of
- 36:04rich countries
- 36:06these are the five richest countries in
- 36:07the database from this paper
- 36:09and then profiles for select poor
- 36:11countries which is the five
- 36:13poorest countries that were in the
- 36:14database for the same paper
- 36:17so the way you read these profiles let
- 36:18me just pick one to start with so this
- 36:20dash gray here the highest one is
- 36:22germany
- 36:23you always estimate a profile so that it
- 36:26starts at zero
- 36:27and then what you're measuring is how
- 36:29much do wages go up as you get more
- 36:31experience and get older
- 36:33and so that's what's being plotted here
- 36:35when you get to five years of experience
- 36:36in germany the wages have gone up by 50
- 36:38percent as you get towards 15 years of
- 36:41experience their wages have gone up by a
- 36:42hundred percent
- 36:44and eventually in germany the highly
- 36:45experienced workers make about 120
- 36:47percent more than brand new workers
- 36:50okay you can see here united states
- 36:52canada france australia you're getting
- 36:54between
- 36:5570 to 120 higher wages as you become
- 36:58experienced
- 36:59on average among rich countries you
- 37:01about double your earnings over your
- 37:02life
- 37:04um just when they're when they're doing
- 37:06these wages what are they using for wage
- 37:08like is it like pre-tax post tax like
- 37:10how are they defining your
- 37:12wage that's going to make a huge
- 37:16difference for something like us versus
- 37:17canada even like
- 37:19yeah so
- 37:23they as we i'm in here somewhere in the
- 37:25at all now but now it's embarrassing
- 37:26because i have to remember
- 37:27i think we're using pre-tax for most
- 37:30countries and the reason is that pre-tax
- 37:31is what is measured in most countries
- 37:33yeah that would seem to that would make
- 37:34sense to me
- 37:36okay thanks yeah
- 37:39um on the right hand side we're doing
- 37:41the same thing we're measuring these
- 37:42same wage profiles but in a group of
- 37:44poor countries and you can see
- 37:46in poorer countries earnings wages go up
- 37:49much less over the course of your life
- 37:51so you know older and experienced
- 37:54workers make
- 37:55maybe 30 more than the youngest workers
- 37:57in those countries
- 38:00so we can show this for as many
- 38:02countries as we can get our hands on so
- 38:03what i'm going to show you now is what
- 38:04is the height of this profile what's the
- 38:06value to having between 20 and 24 years
- 38:09of experience
- 38:10that's what's plotted on the y-axis so
- 38:13basically it's the height of that
- 38:14profile at 20-24 years
- 38:16plotted against gdp per worker
- 38:20and so you can see that that what i just
- 38:21showed you is a fairly persistent
- 38:23finding
- 38:24are richer countries wages go up a lot
- 38:26more
- 38:27over your life as you get more
- 38:28experience and in the poorer countries
- 38:30they go up a lot less and you can see
- 38:32here you know bangladesh vietnam india
- 38:34guatemala earnings are going up by wages
- 38:37go up by about 20
- 38:39as you gain experience over your life
- 38:40not very much
- 38:43now in practice you have to be a little
- 38:46careful about saying that that's
- 38:47definitely human capital
- 38:49right there's many things that could be
- 38:51going on in in in the
- 38:53paper we we talk a lot about other
- 38:55hypotheses of what could be happening
- 38:57here
- 38:58i think a lot of ancillary evidence has
- 39:00come together to lead people to conclude
- 39:02that this
- 39:03probably is human capital that workers
- 39:05are developing more human capital over
- 39:07their lives in rich countries
- 39:09than in poor countries sort of a recent
- 39:12piece of evidence that i like a lot that
- 39:13points in this direction
- 39:14comes from a paper by ma it's all it's
- 39:17brand new it might even be 2021 at this
- 39:19point
- 39:20which looks at how much training workers
- 39:22receive
- 39:23over their lives and so what they do is
- 39:25they collect data from a wide range of
- 39:27countries on
- 39:28the share of workers who get training
- 39:29from their employer
- 39:31and they're plotting what share of
- 39:33workers get training against gdp per
- 39:34worker you can see there's a humongous
- 39:36gradient here
- 39:38in poor countries basically no one gets
- 39:40training from their employers and in
- 39:41which countries maybe half of the
- 39:42workforce typically gets training from
- 39:44an employer
- 39:46that's a function of two things one is
- 39:48that in poor countries many people are
- 39:49self-employed
- 39:50you can't get training from your
- 39:51employer if you're self-employed
- 39:54i think that's still fair though in the
- 39:56sense at least to me it seems like
- 39:57i think it's probably legitimate to
- 39:59think that a lot of self-employed
- 40:00workers aren't learning much as they do
- 40:02their jobs
- 40:02i mean who would they learn it from who
- 40:04would teach them anything
- 40:07the second thing of course though is
- 40:08that even for people who work for
- 40:10employers who work for wages are more
- 40:12likely to get training from their
- 40:13employer in rich countries
- 40:15so i think about this as being one
- 40:16likely culprit for why we see wages
- 40:18rising more over their life maybe
- 40:20workers are getting more training
- 40:21they're doing more investments they're
- 40:22learning more over their lives
- 40:24they actually provide a quantitative
- 40:26theory that suggests this is probably a
- 40:27big component of it
- 40:30if we take oh sorry if we take this
- 40:33as reflecting workers learning more over
- 40:35their lives and rich than poor countries
- 40:37we want to add that into our measure of
- 40:38human capital
- 40:41and i'll do that in a second do these
- 40:44results
- 40:44change dramatically at all if you
- 40:46separate it out between like men and
- 40:48women for example
- 40:49have you done that
- 40:53a little bit but not much surprisingly
- 40:56women have
- 40:57lower returns to experience in almost
- 40:59every country
- 41:02but that is mostly because the potential
- 41:05experience is a less good measure of
- 41:07experience for women than for men
- 41:10men work almost continuously since they
- 41:11graduate women have many more
- 41:13interruptions over the course of their
- 41:15lives
- 41:15right yeah true yeah exactly all right
- 41:19yeah can i ask a question about the uh
- 41:22about this graph actually
- 41:25um i guess is it
- 41:29like you you say that it's not exactly
- 41:34well no sorry uh let me let me reword it
- 41:36i guess are we
- 41:38could it also possibly be that just the
- 41:40there's kind of like a
- 41:42cap to the capacity of a country to use
- 41:44experience of a worker
- 41:46where like in the more rich countries
- 41:51having more experience actually lets you
- 41:53move
- 41:54up like a wrong or a ladder or something
- 41:56but in a poorer country
- 41:58having more experience doesn't really do
- 42:01anything for you
- 42:02if there's less capacity for the
- 42:04country's like
- 42:07uh like tfp to kind of use that
- 42:10experience
- 42:11so i guess i'm like years of experience
- 42:14maybe isn't
- 42:15completely translatable across countries
- 42:19i think that the the paper that we had
- 42:22to read
- 42:22kind of talks about this a little bit
- 42:24the one that you did with hendrix
- 42:28sorry if that was very vague no no i
- 42:30understand exactly what you're driving
- 42:31yet
- 42:32um it's a good question
- 42:35and it's a deep one so if i go back a
- 42:38little bit
- 42:41really this goes back to the production
- 42:43function
- 42:44if you look at this production function
- 42:46it says look
- 42:47there's constant but decreasing returns
- 42:49to capital
- 42:50constant and decreasing returns to human
- 42:52capital they're completely separable and
- 42:53there's really no interesting
- 42:55interactions between these factors here
- 42:57if i double your human capital in the
- 42:59united states you get 2 raised to the 1
- 43:01minus alpha output
- 43:02if i double your human capital vietnam
- 43:04you get 2 raised to the 1 minus alpha
- 43:06extra output it's the same everywhere
- 43:09and then i think i could give you a list
- 43:12of papers and especially it's a common
- 43:14thing to see in the conclusion of a
- 43:15paper to say
- 43:16yeah you know it's really interesting
- 43:17what if there's an important interaction
- 43:19between the technology we have
- 43:21and our ability to use schooling or
- 43:23experience that's an interesting idea
- 43:24for future research
- 43:27and that's kind of where it always
- 43:28lingers okay but that's
- 43:30that's really where this point right
- 43:32here is where you can really see why
- 43:34why i'm not talking about ideas like
- 43:35that it's embedded in the production
- 43:37function right from the very beginning
- 43:40thank you
- 43:44all right i don't want to bore you to
- 43:46death by showing you a million of these
- 43:47things so there's a couple more things
- 43:49that people are going to keep track of
- 43:50time too there's a couple more things
- 43:51that people have looked at
- 43:52including education quality and health
- 43:55would be the two other things you might
- 43:56think about adding into this measure
- 43:59so on the left hand side here i have
- 44:00plotted a measure of education quality
- 44:03which is
- 44:03math scores on the pisa exam which is a
- 44:06very common and very popular exam
- 44:09if your country takes it you'll know
- 44:10about it because they'll report the
- 44:12report they'll report the scores in the
- 44:13newspaper and complain about how you're
- 44:15not doing well enough on it unless
- 44:16you're in singapore or finland where
- 44:18they do great
- 44:19so what's plotted here is the score on
- 44:21math in 2018 and you can see yes people
- 44:23in poor countries score
- 44:24much worse on the math exam
- 44:28health is probably the trickiest thing
- 44:30to measure
- 44:31and again it's like even in the united
- 44:33states you know how do i measure the
- 44:34health of two people
- 44:36that's a very difficult thing so here's
- 44:38one proxy for health
- 44:40adult survival rate that's the
- 44:42probability of the 15 year old will live
- 44:44to 60.
- 44:46and you can see that in rich countries
- 44:47most 15 year olds will live to 60. but
- 44:50if you go to poor countries you know
- 44:51on average maybe only 70 80 percent do
- 44:55we think that's probably correlated with
- 44:57bad health with the prevalence of
- 44:59diseases with their inability to get
- 45:01enough nutrition
- 45:02and to afford proper medicines you know
- 45:05it's not ideal measure but that's what
- 45:06we have to work with
- 45:10you can see though that as we go along
- 45:11in this constructive method
- 45:13you know what's the value of 50 points
- 45:15of ps of math score
- 45:17for productivity now we're starting to
- 45:20get this is getting a little tricky this
- 45:22gets a little harder and i'm going to
- 45:23show you the papers that have done this
- 45:24in a second
- 45:25but this is more challenging what's the
- 45:28value
- 45:28in terms of productivity of living in a
- 45:30country where you have 0.1 higher adult
- 45:32survival rate
- 45:35okay people continue to build on those
- 45:38minster wage equations and they have you
- 45:39know approaches and tricks in back of
- 45:41the envelope calculations to make that
- 45:42happen
- 45:43so let me show you what those results
- 45:44are
- 45:46what i'm going to do here is accumulate
- 45:48one step at a time
- 45:50a measure of human capital so i'm going
- 45:51to construct it literally as the
- 45:53literature has done over time
- 45:55and i'm going to ask how important is it
- 45:56for cross-country income differences
- 45:58using this covariance metric
- 46:01so i told you before if you measure
- 46:03human capital as years of schooling
- 46:04you're going to
- 46:05you're going to explain or account for
- 46:06about 19 percent of income differences
- 46:10if you add quality of schooling sort of
- 46:13a typical
- 46:14estimate is that that's actually about
- 46:15as important as the years of schooling
- 46:18for cross-country income differences
- 46:19that'll get you to about 38
- 46:22and i don't know if this is coincidence
- 46:24or not but when you add experience you
- 46:25almost always get about another 18 to 19
- 46:28percent here it's 18
- 46:31so this is 56 health
- 46:34the leading estimates of health are that
- 46:36it's much less important which
- 46:38i don't know i just always feel like
- 46:39it's important but anyway i have no i
- 46:41have no evidence i've never done any
- 46:42research i feel like it should be more
- 46:44important than that but i i've never
- 46:45proved it
- 46:46and someone said that schooling
- 46:48experience health we're up to maybe like
- 46:4959
- 46:50of cross country more than half of
- 46:52cross-country income differences are due
- 46:53to health if we add it up this way
- 46:55here's your list of references if you
- 46:57click on them they'll take you to the
- 46:58right papers to see
- 46:59see where these estimates come from
- 47:02being part of health is accounted for
- 47:04indirectly through like schooling
- 47:05experience like if you don't have good
- 47:07health then you're not going to school
- 47:11yep give me one second that's the next
- 47:12slide it's exactly i'm going to
- 47:14summarize
- 47:14and that's exactly what i'm concerned
- 47:15about
- 47:17so this first approach which i'm going
- 47:19to be done with now
- 47:21uh measures cross-country human capital
- 47:23differences constructively like
- 47:24literally constructing building it piece
- 47:26by piece
- 47:28you account for differences in stocks or
- 47:30rates of return
- 47:32and those resulting estimates are large
- 47:33maybe 60 percent of income differences
- 47:35but
- 47:35you know i think you should have some
- 47:36concerns at this point you should not be
- 47:38satisfied or happy with what we've done
- 47:41one thing is you have to be worried
- 47:42about those assumptions so here's a
- 47:44reference to the first paper that starts
- 47:45to rethink those assumptions we use for
- 47:47development accounting there's a whole
- 47:48literature that builds from him but he
- 47:50was the first
- 47:52the other two concerns just kind of
- 47:54conceptually it's hard to be exhausted
- 47:58what i mean by exhaustive is do i think
- 48:00we've accounted for or measured all of
- 48:02the different pieces of human capital
- 48:04probably not right i mean we added up
- 48:06years of schooling quality of schooling
- 48:08experience health if there's anything
- 48:09else that's not in there
- 48:11so we might imagine this number could be
- 48:13even bigger
- 48:14but at the same time and this is what is
- 48:16it jolene is that who that was
- 48:18yeah okay good um we may be double
- 48:20counting here
- 48:22right because health might very well
- 48:26affect the quality of schooling that a
- 48:27country has if the students have better
- 48:29health they may do better on the tests
- 48:30and that may show up as better quality
- 48:31of schooling
- 48:33likewise you know being in school a long
- 48:35time may help you learn more on your job
- 48:37so when i add up the value of schooling
- 48:39and the value of experience i may have
- 48:40counted something twice
- 48:42because some of the value you having
- 48:43experienced may have come from your
- 48:44schooling
- 48:45and so there's a concern here that by
- 48:47adding things up this way i may be
- 48:49misattributing miscounting or double
- 48:51counting things
- 48:54that's going to lead me to my second
- 48:56approach which i'm going to call the
- 48:57deductive approach
- 48:58so are there any questions before i meet
- 49:02um excuse me
- 49:07yeah hello prof yep somebody go
- 49:12hey hello i hear you yeah look
- 49:16yeah hello i have a little bit of
- 49:18question respect to a recent port
- 49:20contrary especially technological uses
- 49:22and that of that with the taste
- 49:24so in terms of measuring uh the human
- 49:27capital specifically in
- 49:29most of the developing countries like
- 49:31you gave an example like in ghana and
- 49:33other different countries and etcetera
- 49:34don't you think that the taxonomy
- 49:36might be perhaps determined more easily
- 49:39based on the technological uses
- 49:41that the people have within the country
- 49:43they say because i think uh with the use
- 49:45of technology
- 49:46the technical know-how especially in
- 49:48this uh
- 49:49environment of uh intensive uh economic
- 49:53that we are in so with all
- 49:54i mean uh the technical uses uh how do
- 49:57you think that poor control regardless
- 49:58of violence
- 49:59especially in the cultural project in
- 50:00terms of converging bigger convergence
- 50:03uh it is possible whenever poor
- 50:06countries are trying to educate the
- 50:07populations
- 50:08because i think there is always a peak
- 50:11in most of the western nations
- 50:12especially developed country
- 50:13and as a result agenda is always an
- 50:15opportunity for the poor country to
- 50:17catch up because they're convergent
- 50:18but how would they catch up when they in
- 50:21terms of the transfer of technology
- 50:23rnd i mean research and development is
- 50:26not advanced
- 50:27and the taxonomy issues also has a
- 50:30little bit of gap
- 50:31so with respect to the quality of
- 50:33education so what
- 50:35are some of the research you think that
- 50:36may be appropriate to ensure that
- 50:38an advancement or most of the least
- 50:39developing country can able to catch up
- 50:41more faster
- 50:44okay that was a lot to chew on um i
- 50:46think
- 50:48i heard two distinct questions and you
- 50:50can let me know if i missed something
- 50:53one thing i heard was um a general
- 50:55question about the interaction between
- 50:57human capital and technology
- 50:59yeah and i think my answer is going to
- 51:02be the same as the answer i gave a
- 51:03minute ago which is that if you look
- 51:05right here
- 51:06technology is a part of tfp here's human
- 51:09capital
- 51:11if you look at this you'll see that
- 51:13there are no really interesting
- 51:14interactions between these two things
- 51:16having more technologies good having
- 51:18more human capital is good but there's
- 51:20not really
- 51:21there's no idea that you have to have
- 51:23technology to make use of skills
- 51:25there's no idea that having skills makes
- 51:26technologies more valuable
- 51:29in everything i've done so far that's
- 51:30been missing if you send me an email
- 51:33i'll send you i mean there is
- 51:34very recent work that's trying to
- 51:36investigate these things like how much
- 51:37does technology
- 51:38aid the use of human capital and vice
- 51:40versa
- 51:42that's really frontier work at this
- 51:44point so i would say it's not very
- 51:45subtle that's why i didn't want to teach
- 51:47it but
- 51:47people are thinking about it the second
- 51:49piece was you know if
- 51:51education quality is important how do i
- 51:53get more of it i think that's the way i
- 51:54would interpret that question
- 52:00the uncomfortable and sad truth about
- 52:02this literature is that no one knows
- 52:04i can point you to some books and some
- 52:06papers and reports
- 52:08that's not really something that
- 52:11what's a polite way to say i'm somebody
- 52:15who's worked on this and i'll say it
- 52:16about myself
- 52:17that's not something my research has
- 52:18ever been very good at
- 52:21i can tell you that it's important but
- 52:22if you ask me like at a nitty gritty
- 52:24level what should i do in our schools to
- 52:26make sure that they actually get this
- 52:27quality that seems so important
- 52:28my papers are completely useless on that
- 52:30part that's the truth
- 52:33um i can point you to some manuals and
- 52:35like if you read the
- 52:36pisa reports they'll give you some ideas
- 52:38or best practices of countries i don't
- 52:40know how reliable those are but that's
- 52:41the best that's out there truthfully
- 52:44because what made me to have asked the
- 52:46question is simply because i'm also
- 52:48writing my uh this irritation solution
- 52:50on human capital development it will
- 52:51develop
- 52:52in developing countries so but uh i came
- 52:54across some uh
- 52:56i mean some issue with respect to the
- 52:59i mean the country productivity based on
- 53:02mainframe
- 53:02that stays to this stage that is to say
- 53:05from the
- 53:06before the turns after another
- 53:07advancement like in asia example like in
- 53:09korea
- 53:10like people select taiwan you know they
- 53:12started with uh radio activities like a
- 53:15radio receiver and all the different
- 53:18things you know before they try to
- 53:19advance
- 53:20but in the same vein and in certain
- 53:21countries in asia and so like malaysia
- 53:24where i'm stationed currently and
- 53:25basically china
- 53:27they were not advanced and typically
- 53:29compared to other countries like ghana
- 53:31was empowered with other korea
- 53:33by the end of the day ghana left behind
- 53:35malaysia has advanced
- 53:36korea has very intense technology i
- 53:39believe that technology i mean observe
- 53:42like a sort of leaf rock
- 53:43of the economy like in india okay
- 53:46because of
- 53:47the incremental human capital in india i
- 53:49think they tried to refrog
- 53:51we're in it of living over world today
- 53:53so if
- 53:54maybe a technology vis-a-vis human
- 53:56capital a main
- 53:58improvement or advancement per se can
- 54:00can be uh somewhat depressed let's say
- 54:02because
- 54:02we have different processes in terms of
- 54:04human capital such as f as is one of the
- 54:05deposited percent
- 54:07and income is one of them but can we
- 54:09measure the gdp per capita
- 54:11based on the individual percent based on
- 54:15the popular educated population within a
- 54:17country
- 54:18or based on the input of the country the
- 54:20total production
- 54:21part of a dpf so total factor of
- 54:24production tpf
- 54:26tft runner
- 54:30sorry i don't think i understood that
- 54:32question yeah what i try to say is that
- 54:35can we measure the country gdp
- 54:39i think we're going to have to go on i'm
- 54:41sorry okay
- 54:42okay
- 54:46if asked me again during the during the
- 54:48follow-up session i'm just not quite
- 54:49sure i'm grasping it um
- 54:52can i make a quick question yes please
- 54:55um so is there a sense here um we're
- 54:58making a causal statement
- 55:00somehow so we're saying human capital
- 55:01causes gdp to be larger
- 55:03but it can also be true that um richer
- 55:07countries have
- 55:08like more opportunities to increase
- 55:10human capital right because it's not
- 55:12only valuable
- 55:13for develop as a productive resource
- 55:16and thinking in cases such as latin
- 55:19america where
- 55:20like recently the like the fiscal
- 55:23government like the
- 55:24the country governments make a huge
- 55:26effort to increase education
- 55:28in all levels and it was only possible
- 55:30because the countries were
- 55:32a bit richer than before or they
- 55:34experience some kind of commodity bloom
- 55:35etc
- 55:37so right from the beginning actually
- 55:39this has been an obsession in this
- 55:41literature and
- 55:42if you go back and read bills in
- 55:43greenhouse paper the people who worked
- 55:45out these assumptions that we're using
- 55:47you'll see that that was exactly what
- 55:48they were wondering which is does
- 55:50getting more schooling make you rich
- 55:51or does getting richer lead you to get
- 55:52more schooling
- 55:54what i'm going to say today and the way
- 55:56i try to phrase these slides i sometimes
- 55:58mess up on this is we always try to say
- 55:59that
- 56:00human capital accounts for a lot of
- 56:03cross-country income differences
- 56:05and then that's a fancy way of saying we
- 56:07don't know where the schooling comes
- 56:08from
- 56:09it could be that tfp leads people to get
- 56:11more schooling and
- 56:12leads them to get richer i'm not going
- 56:15to be able to make a statement
- 56:16that's causal i'm trying not to make any
- 56:18causal statements
- 56:19it just seems like there are really
- 56:20large differences across countries in
- 56:22human capital
- 56:23and we want to think about that more
- 56:29all right so the second approach uh that
- 56:31i kind of want to investigate a little
- 56:32bit is going to be called
- 56:33the deductive approach and this is built
- 56:36on the idea that
- 56:37human capital you know by my definition
- 56:39at least is embedded in people
- 56:42and so what we're going to do is we're
- 56:43going to utilize the fact that migrants
- 56:46of which there are many carry their
- 56:48human capital to new countries when they
- 56:49move
- 56:50okay and so this is going to allow us
- 56:52the opportunity to deduce the importance
- 56:54of human capital
- 56:56what's different about this is that
- 56:57we're not going to try to specify what
- 56:59human capital is or to build it up piece
- 57:01by piece we're just going to say
- 57:03whatever
- 57:03human capital is the migrant has it when
- 57:06they move they take it to the new
- 57:07country let's see how important it is in
- 57:09that new country
- 57:11so if you remember you know the wages we
- 57:14specified under those maintained
- 57:15assumptions were that the log wage of a
- 57:17worker with human capital i in country c
- 57:20is additive and a country effect and a
- 57:22human capital effect
- 57:24and so the way i want you to think about
- 57:25this is well if i have a worker who
- 57:27migrates they take that human capital
- 57:29they used to have a country with this z
- 57:31they move to a country with a new z
- 57:32and that's going to give me some
- 57:33opportunity to see how they do
- 57:36even more intuitively the way i like to
- 57:38think about this is
- 57:41in general what would be really cool is
- 57:43if we could take the united states and
- 57:44give the united states the human capital
- 57:46investments of ghana
- 57:47and then say how does that affect the
- 57:49united states now of course we don't get
- 57:51you know we're macro economies we don't
- 57:53get to do randomized trials on entire
- 57:54countries
- 57:56but an immigrant gives us the best shot
- 57:58we have because we can see somebody with
- 57:59ghanaian human capital move to the
- 58:01united states and see how they do
- 58:04and that's kind of the underlying idea
- 58:06behind this exercise
- 58:08now of course there's a trade-off
- 58:09nothing comes for free in economics
- 58:11since we're going to be talking about
- 58:12migrants we have to deal with two
- 58:13additional concerns that are just going
- 58:15to be pervasive throughout this
- 58:16literature that thinks about migrants
- 58:18and human capital
- 58:19which is that the migrants of course are
- 58:21not randomly chosen you have to worry
- 58:22about the fact that they're selected
- 58:24they may be different than the random
- 58:25ghanaian
- 58:27and the second is that their human
- 58:28capital may not be fully portable
- 58:30right if you look at this equation what
- 58:32i'm thinking to myself is well if they
- 58:33take this human capital to another
- 58:35country what happens
- 58:37but of course the skills and the
- 58:38knowledge they have may not be as useful
- 58:40in the new country they may be the wrong
- 58:42type they may be discriminated against
- 58:43all of those types of concerns have to
- 58:45be dealt with
- 58:47okay so there's been a
- 58:50at the bottom here i talked i gave you
- 58:52some references for other papers there's
- 58:53a there's a
- 58:55sort of a small literature but a long
- 58:57one that long has been going on for
- 58:59about 20 years that investigates this
- 59:00idea
- 59:01the approach i'm going to show you today
- 59:03and that i recommended for the reading
- 59:05was to think about what are the wage
- 59:06gains at migration
- 59:08okay so the idea here is imagine that i
- 59:10could see
- 59:12the wage of a worker who moves from c
- 59:15to c prime both after he migrates and
- 59:18before he migrates
- 59:21if i go back and take this wage equation
- 59:23and just take the first difference of
- 59:25this just difference across two
- 59:26countries that worker has the same human
- 59:28capital in both countries
- 59:29so that's going to drop out and what i'm
- 59:32going to be left with is just
- 59:33the z the difference in z's between the
- 59:35two countries
- 59:37but that's exactly one of the two things
- 59:39i wanted to understand from my
- 59:41development accounting exercise which is
- 59:42how big is the
- 59:43z difference across countries
- 59:47so this would be a really easy way to
- 59:49quantify one piece of the development
- 59:51accounting puzzle
- 59:53the underlying intuition here i like to
- 59:55just say this like plainly
- 59:57suppose i have a worker who migrates
- 59:59from a poor to a rich country let's say
- 1:00:00the rich country is 10 times richer and
- 1:00:02make everything easy
- 1:00:04if that workers wages went up by a
- 1:00:06factor of 10
- 1:00:07i would say wow switching countries
- 1:00:09fixed everything it made this worker
- 1:00:10much richer
- 1:00:11it must be that country is what matters
- 1:00:14something about the institutions the
- 1:00:17capital the infrastructure i don't know
- 1:00:19but changing countries fixed everything
- 1:00:21i'm going to conclude that z must be
- 1:00:22what matters for cross-country income
- 1:00:24differences
- 1:00:26on the other hand suppose that that
- 1:00:27worker switches countries and their
- 1:00:29wages don't move at all they stay really
- 1:00:30low
- 1:00:32well then i would say boy the country
- 1:00:33didn't do anything the country must not
- 1:00:35really matter much for the wage this
- 1:00:36worker receives
- 1:00:38boy it seems like their low human
- 1:00:39capital must explain why they have such
- 1:00:41low wages
- 1:00:44now you'll notice that that really
- 1:00:45hinges crucially on
- 1:00:47thinking about who these workers are and
- 1:00:48whether their skills fully transfer and
- 1:00:50in the paper
- 1:00:51i'm going to try to get through this
- 1:00:52relatively quickly so i can show you a
- 1:00:54little bit of models
- 1:00:55in the paper we do try to do some
- 1:00:57exercises to think about how big those
- 1:00:59effects are but i want to kind of get to
- 1:01:00the main results to show you
- 1:01:02what's different about this let me
- 1:01:05emphasize this one more time
- 1:01:06this is almost like a completely
- 1:01:08different way to come at the same
- 1:01:09problem
- 1:01:10because here i'm not going to try to
- 1:01:12specify what human capital is
- 1:01:14i'm not going to try to specify how they
- 1:01:16got it or what attributes of it are
- 1:01:18important
- 1:01:19i'm just going to say whatever they have
- 1:01:20they're going to take it to two
- 1:01:21different countries
- 1:01:23and that's going to let me to think
- 1:01:24about how big the z differences are
- 1:01:25that's what i mean by deductive
- 1:01:27it's like i'm going to deduce based on
- 1:01:29how much their wages change how
- 1:01:30different human capital must be
- 1:01:34you need the the kind of one tricky
- 1:01:36thing for this is that
- 1:01:37you need data where you know how much
- 1:01:39workers how much wages workers made
- 1:01:42before and after they migrate
- 1:01:44most data sets don't have that so here's
- 1:01:46a couple of data sets we found that did
- 1:01:48that's what we're going to use to
- 1:01:49quantify this and all we do in this
- 1:01:51paper
- 1:01:52is just convert wages to ppp adjusted
- 1:01:54wages
- 1:01:55and then we're just going to ask how
- 1:01:56much do ppp adjusted wages change
- 1:01:59relative to pppgd people worker gaps
- 1:02:02that's the notion of how much does your
- 1:02:03wage go up how much is the country
- 1:02:05matter
- 1:02:09and then what i've highlighted here is
- 1:02:11sort of the main results from that paper
- 1:02:13what we find is that workers from
- 1:02:15countries that are less than a sixteenth
- 1:02:17as rich as the united states so these
- 1:02:19are the very poorest countries
- 1:02:20immigrants come from to the united
- 1:02:21states when they move
- 1:02:22they get about three times higher wages
- 1:02:26the gdp gap between those countries in
- 1:02:28the united states on average is a factor
- 1:02:30of 32.
- 1:02:32so switching countries makes them richer
- 1:02:34right their wages go up by a factor of
- 1:02:36three but that's a small amount relative
- 1:02:38to the total gdp gap
- 1:02:40and so when you do it you'll find that
- 1:02:41that would imply that human capital
- 1:02:43accounts for about two-thirds of
- 1:02:44cross-country income differences
- 1:02:47you can do the same thing for different
- 1:02:49groups we have two different data sets
- 1:02:52but as a whole when we do this we
- 1:02:53consistently find that workers wages go
- 1:02:56up by
- 1:02:56a small amount relative to the gdp gap
- 1:03:00and that that would imply that human
- 1:03:01capital accounts for something like 60
- 1:03:04of income differences 50 to 60 percent
- 1:03:14so the deductive approach i think has
- 1:03:16strengths and weaknesses relative to the
- 1:03:18constructive approach it's exhaustive
- 1:03:19because it measures whatever human
- 1:03:21capital is wherever it comes from
- 1:03:23but it's not constructive and so
- 1:03:26somebody already asked me you know if
- 1:03:27education quality is so important how do
- 1:03:29i get it you can see that this is even
- 1:03:30worse now right this one is like if
- 1:03:32human capital is so important
- 1:03:33where do i get it from you know this
- 1:03:36would really not be very helpful for
- 1:03:37that
- 1:03:38it avoids double counting it does
- 1:03:41require these additional assumptions
- 1:03:42about migrants and i'm going to refer
- 1:03:44you to the paper if you want to ask
- 1:03:46questions you know
- 1:03:46that's it honestly it takes a whole
- 1:03:48seminar but i'm going to present the
- 1:03:49paper and really talk through all of
- 1:03:51that it's it's
- 1:03:52anyway what i like about it is that
- 1:03:54although it comes from a completely
- 1:03:56different direction you end up getting
- 1:03:57fairly similar
- 1:03:58results you get the human capital
- 1:03:59accounts for half to maybe 60 percent of
- 1:04:01income differences
- 1:04:03okay and so we have two different ways
- 1:04:05of getting to the same point
- 1:04:07both of us lead to think that human
- 1:04:08capital is really big i still think
- 1:04:10there's room to explore on the
- 1:04:12measurement side
- 1:04:13sort of my pet peeve with this whole
- 1:04:15literature is that
- 1:04:16we're really talking about measurable
- 1:04:18stuff we're not really talking much
- 1:04:19about skills
- 1:04:20i would really love to know more about
- 1:04:22what exact skills are missing in poor
- 1:04:24country like
- 1:04:25they don't go to school as long and the
- 1:04:26schools aren't as good so they don't
- 1:04:28know how to do
- 1:04:29what what specifically is it that they
- 1:04:31miss when they go to the job i've never
- 1:04:33had any sense that i know what that is i
- 1:04:34would love to know more about that
- 1:04:37anyway i think there's more to be done
- 1:04:39on the measurement side what i would
- 1:04:40like to do now let me see how am i doing
- 1:04:42on time
- 1:04:43yeah about what i expected what i'd like
- 1:04:45to do now is show you a little bit of
- 1:04:46models about human capital differences
- 1:04:48and the idea here is if you are
- 1:04:50convinced or at least intrigued to think
- 1:04:52that human capital
- 1:04:54might be vary a lot across countries and
- 1:04:56it might be a big piece of the
- 1:04:57development puzzle and also of the
- 1:05:00differences in across sectors during
- 1:05:02structural transformation
- 1:05:03you'd want to build that into your model
- 1:05:05how do you do that what is like the
- 1:05:07off-the-shelf simplest model you would
- 1:05:09start with
- 1:05:10so i'm going to give you a very simple
- 1:05:12version of these models
- 1:05:13and then give you references if you want
- 1:05:15to go and dig in and do the fuller
- 1:05:16bigger versions of them all
- 1:05:25all right so the goal here is mostly i
- 1:05:28first and foremost i want to illustrate
- 1:05:30the mechanisms that can help you explain
- 1:05:31these large human capital differences
- 1:05:34all right and the way you want to think
- 1:05:35about this is human capital as i've been
- 1:05:37emphasizing is an investment that people
- 1:05:39make
- 1:05:40people in rich countries are investing
- 1:05:41more that accounts for a lot of
- 1:05:44cross-country income differences but it
- 1:05:45doesn't explain it to explain it i would
- 1:05:47want to know
- 1:05:48why why do they invest more so what i
- 1:05:51want to do is give you some models
- 1:05:52i'm going to start with a benchmark
- 1:05:54model that can't explain it which is a
- 1:05:56useful result like oh if i do that i'm
- 1:05:57not going to get anywhere
- 1:05:59then how do i tweak that model to
- 1:06:00explain some of the differences
- 1:06:02all right this is the simplest way i
- 1:06:06could think of to write this model down
- 1:06:08so let's start with the firm it's a
- 1:06:10representative form so you can think of
- 1:06:11it as a bunch of firms if you want
- 1:06:13the firm is exactly what i showed you
- 1:06:15before nothing new here
- 1:06:17they operate this cobb douglas
- 1:06:19production function it's the same one i
- 1:06:20showed you
- 1:06:22i'm going to insist on the same two
- 1:06:23assumptions perfect substitution
- 1:06:25competitive labor markets
- 1:06:27that's going to give me the same wage
- 1:06:28equation i had before nothing new on the
- 1:06:31firm side
- 1:06:34what i want to do now is add a model of
- 1:06:36the worker
- 1:06:38really the person who's making decisions
- 1:06:41about investments
- 1:06:42and think about what would lead their
- 1:06:45decision about how much to invest to
- 1:06:46vary across countries
- 1:06:49so here's the simplest model this really
- 1:06:50is a dumbed down version of becker's
- 1:06:53book
- 1:06:54so let's have a consumer who lives for
- 1:06:56one unit of time
- 1:06:58and they're going to maximize utility
- 1:07:00and the utility is just i'm going to
- 1:07:02integrate over that period
- 1:07:04i have log preferences i have
- 1:07:06consumption of t
- 1:07:07at every instant t during that one unit
- 1:07:09of time
- 1:07:12and then they're going to decide their
- 1:07:14consumption profile
- 1:07:15the other choice they're going to get to
- 1:07:16make is how long they go to school
- 1:07:18before they start working
- 1:07:20so the simplest version possible of this
- 1:07:22is to say all right they're going to
- 1:07:23attend school for a length of time
- 1:07:25s schooling develops human capital so
- 1:07:28when they leave school they're gonna
- 1:07:30have human capital h of s
- 1:07:32the remaining unit of time one minus s
- 1:07:35they're going to go to work
- 1:07:36and they're gonna earn a wage then their
- 1:07:39budget constraint simply says that the
- 1:07:41integral
- 1:07:42of their consumption has to be equal to
- 1:07:44their income
- 1:07:45right the money to finance what they
- 1:07:47consume has to come out of their income
- 1:07:50and then their income piece by piece
- 1:07:53this is the z from the wage equation so
- 1:07:57literally i'm just copying the wage
- 1:07:58equation to start with
- 1:08:00right i'm plugging in their human
- 1:08:02capital that's a function of
- 1:08:03how long they go to school and then how
- 1:08:05much do they get to work well only one
- 1:08:07minus
- 1:08:08s of their life the rest of their time
- 1:08:10they spent in school
- 1:08:13if this is your model of the human
- 1:08:15capital choice you're going to get two
- 1:08:17main results this is this is well known
- 1:08:18from
- 1:08:19becker's book the first result you're
- 1:08:21going to get is that workers in this
- 1:08:23model or people really want to smooth
- 1:08:25their consumption over their life
- 1:08:27in this model i've assumed that people
- 1:08:28don't discount across the period
- 1:08:31or within the period so their
- 1:08:32consumption is exactly the same over
- 1:08:34their life they basically spend their
- 1:08:36income
- 1:08:36smoothly over the course of their life
- 1:08:41the second result that you're going to
- 1:08:42get is what's the optimal school choice
- 1:08:44so just take the first order condition
- 1:08:46and it really naturally gives you an
- 1:08:48equation that says the marginal benefit
- 1:08:50is equal to the marginal cost
- 1:08:52what's the marginal benefit of going to
- 1:08:54school well this first piece here
- 1:08:58is the wage you get for working one
- 1:09:01minus s periods
- 1:09:03the benefit says well i have a little
- 1:09:04more human capital if i go to school a
- 1:09:06little bit longer i'm going to have
- 1:09:07marginally more human capital that's
- 1:09:08going to marginally increase my earnings
- 1:09:12what's the cost of getting a little more
- 1:09:13schooling well this is the wage i could
- 1:09:16have earned during that instant
- 1:09:17right i could have made h of s instead
- 1:09:20but i spent that extra instant going to
- 1:09:22school and getting more human capital in
- 1:09:23the future
- 1:09:24that's the trade-off that a worker faces
- 1:09:26in this model should i get a little more
- 1:09:28human capital
- 1:09:29and get that benefit over the remaining
- 1:09:31one minus s
- 1:09:32or should i just go to work and enjoy
- 1:09:35extra earnings for that instant
- 1:09:39now what's really neat about this model
- 1:09:41uh is that if you look at it carefully
- 1:09:44the one minus alphas and the zcs cancel
- 1:09:47they're on both sides of the equation
- 1:09:50and so that tells me that the optimal
- 1:09:51school choice
- 1:09:52in this model is independent of z this
- 1:09:55is an idea that shows up in becker's
- 1:09:56book already i've always called this
- 1:09:58becker neutrality
- 1:10:01from our perspective this is a problem
- 1:10:05right we're trying to understand why
- 1:10:06people in different countries are
- 1:10:08investing different amounts in schooling
- 1:10:09and there's nothing about the country
- 1:10:11left
- 1:10:12so this is a theory that gets us nowhere
- 1:10:14i like it because it's a benchmark it
- 1:10:16says all right if i start with this
- 1:10:18model
- 1:10:18i can see that i'm going to go astray so
- 1:10:20i need to tweak something here i'm going
- 1:10:21to give you some ideas about what to
- 1:10:23tweak in the next few minutes
- 1:10:25but i want you to understand the
- 1:10:26intuition for this because i think it's
- 1:10:27really powerful
- 1:10:29so what's going on here imagine i live
- 1:10:32in a country with a better
- 1:10:33government or better institutions or
- 1:10:35technology or whatever your favorite
- 1:10:37theory of tfp is
- 1:10:40i think most of us kind of intuitively
- 1:10:42would say ah well if there's a better
- 1:10:44technology it makes it more beneficial
- 1:10:46to invest in human capital right
- 1:10:48but if you look up here what this tells
- 1:10:50us is that yes the benefits of human
- 1:10:52capital investment go up
- 1:10:54right because i'm going to earn more off
- 1:10:56my human capital investment
- 1:10:58but in this model the other force that
- 1:10:59shows up is that if i live in a country
- 1:11:01with a higher tfp better technology
- 1:11:03whatever it is
- 1:11:04that also raises the cost because i
- 1:11:06could have earned higher wages during
- 1:11:08the time i spent in school
- 1:11:10and those two things exactly cancel
- 1:11:13okay and so the underlying idea here is
- 1:11:15that if
- 1:11:17time my time
- 1:11:20is the main investment i put into human
- 1:11:24capital
- 1:11:26then the opportunity cost of my time is
- 1:11:28proportional to z
- 1:11:29the benefit of my time is proportional
- 1:11:31to z that's not going to get me very far
- 1:11:35all right so now how can we tweak this
- 1:11:37and there's going to be
- 1:11:38i think i have time to do all three let
- 1:11:39me check my time one last time might
- 1:11:41have to cut one off there's three main
- 1:11:42ways that the literature is used maybe
- 1:11:44four
- 1:11:45to tweak this model so we can start to
- 1:11:47get some actions we can start to get
- 1:11:49cross-country differences in human
- 1:11:50capital
- 1:11:51and so if you're building a model of
- 1:11:52human capital i think you want to make
- 1:11:54sure you have some of these elements
- 1:11:56one is borrowing constraints
- 1:12:00go back and look at what i said maybe
- 1:12:02you didn't notice it
- 1:12:03it sneaks by people a lot what agents in
- 1:12:06this model want to do is they want to
- 1:12:08consume smoothly over their life
- 1:12:11including while they're in school where
- 1:12:13does the money for that come from
- 1:12:16well the way this model is written in
- 1:12:18the bar
- 1:12:19in the budget constraint you're allowed
- 1:12:22to borrow as much as you want
- 1:12:24there's perfect credit markets so the
- 1:12:27first thing you can do is say well
- 1:12:29i'm not so sure about that i think
- 1:12:32there's actually probably a lot of
- 1:12:33limits to the ability of children and
- 1:12:35their parents to borrow and finance
- 1:12:37these investments
- 1:12:39and i've listed here some of the major
- 1:12:41impediments you know in general i think
- 1:12:42most of us know that credit markets
- 1:12:44aren't perfect
- 1:12:45that it's hard for people to borrow
- 1:12:47large sums of money to finance all of
- 1:12:48their consumption and expenditures on
- 1:12:50schooling
- 1:12:52particularly since we don't let children
- 1:12:53write contracts
- 1:12:56we don't let them sign binding contracts
- 1:12:57right hi i'm 14 i'd like to borrow the
- 1:13:00money so i can go to heist to a really
- 1:13:01good high school to benefit myself over
- 1:13:03my life
- 1:13:04you know we don't let people sign a
- 1:13:06contract that agrees that they'll repay
- 1:13:07that
- 1:13:10you might be able to work around that if
- 1:13:11you think oh well the parents can invest
- 1:13:13on the behalf of the children
- 1:13:16but that requires that parents be really
- 1:13:17altruistic towards their children
- 1:13:19okay and so if you go and read becker
- 1:13:21and tones this is a beautiful paper in
- 1:13:23the journal of labor economics that just
- 1:13:24works through exactly what you would
- 1:13:26need
- 1:13:26in terms of altruism or credit markets
- 1:13:30to get the socially optimal investment
- 1:13:32and
- 1:13:33they're pretty tough restrictions
- 1:13:36for our purposes since we're trying to
- 1:13:37think about cross-country human capital
- 1:13:39differences the main idea you would want
- 1:13:41is
- 1:13:41maybe people in poor countries have a
- 1:13:43harder time borrowing
- 1:13:45and that seems like a pretty natural
- 1:13:46restriction if they have a harder time
- 1:13:48borrowing in poor countries
- 1:13:51because the credit markets aren't as
- 1:13:52good or because their parents can't
- 1:13:54borrow on their behalf
- 1:13:55or because you know they're they're
- 1:13:58they're near a subsistence constraint
- 1:13:59consumption is really low
- 1:14:01any of those types of mechanisms um then
- 1:14:04what you're going to get is that people
- 1:14:05in poor countries are going to have less
- 1:14:06schooling because they literally just
- 1:14:07can't borrow enough that's one force
- 1:14:09that you could put in the model
- 1:14:11and hello and um
- 1:14:15i think perhaps it's also impossible to
- 1:14:19hedge against unemployment after getting
- 1:14:22the education
- 1:14:26yes um or more generally there's a
- 1:14:30there's a literature um tom krebs
- 1:14:33is the big reference for this about
- 1:14:35human capital risk that you can't
- 1:14:36there's no way to hedge against risk we
- 1:14:38often talk about human capital as if
- 1:14:40go to college in the united states and
- 1:14:42you get sixty percent higher earnings
- 1:14:43but of course there's a huge thing
- 1:14:45yeah okay yeah yeah but there is no
- 1:14:48possibility of putting that in this
- 1:14:50model for example
- 1:14:52yeah no i mean
- 1:14:56like i said if you go read krebs uh
- 1:14:58krebs and write
- 1:14:59send me an email and i'll send you the
- 1:15:01exact papers people have put these into
- 1:15:02models nobody in macro development that
- 1:15:04i know of
- 1:15:06so there's a literature in the united
- 1:15:07states for example that says you know
- 1:15:09americans might not be willing to borrow
- 1:15:11for college because of this risk
- 1:15:13i don't know anybody who's taken that
- 1:15:15across countries yet i think that's kind
- 1:15:16of the current state of the literature
- 1:15:18that would be an interesting idea yeah
- 1:15:20because the and
- 1:15:21this is quite different if you look at
- 1:15:23the trend of what is happening in many
- 1:15:25developing countries
- 1:15:26in developing countries there is a
- 1:15:28growing uh commercialization of
- 1:15:30education
- 1:15:31especially at high school level people
- 1:15:33spend a lot of money
- 1:15:34acquiring education and and usually
- 1:15:38without credit
- 1:15:41and i i really have not really seen
- 1:15:45so much in terms of return to that uh
- 1:15:48such investment because this is an
- 1:15:50environment where you have
- 1:15:52very high unemployment rate and all of
- 1:15:54that uh
- 1:15:55so i i i i like to get the
- 1:15:58paper maybe that way it's a proposition
- 1:16:02that
- 1:16:02if maybe governments will be able to put
- 1:16:06in some better policy if it is possible
- 1:16:08to hedge against
- 1:16:09unemployment after making those
- 1:16:11investments in human capital
- 1:16:12yeah yeah if you send me an email my
- 1:16:15name is my email address
- 1:16:17basically my name at gmail i'm easy to
- 1:16:18find okay i'll send you that paper i
- 1:16:20want to say one thing real quickly
- 1:16:21though
- 1:16:23there's a distinction between two things
- 1:16:24one is just risk
- 1:16:26i don't know if i'll find a job i don't
- 1:16:28know if the job will pay i don't know if
- 1:16:30my degree is valuable there's a great
- 1:16:31literature on that
- 1:16:32there's a second phenomenon which is
- 1:16:34kind of strange in some developing
- 1:16:35countries where
- 1:16:37the college graduate unemployment rate
- 1:16:38might be 50
- 1:16:40yeah that's not risk
- 1:16:45that's like a misallocation i don't
- 1:16:47think anybody has i don't know i've not
- 1:16:48seen a good i've always been
- 1:16:50confused like crazy about that and i
- 1:16:52don't have any good models why that
- 1:16:54would be
- 1:16:55so anyway that would be so if somebody
- 1:16:57could explain to me just at a really
- 1:16:58basic level what's going on there i have
- 1:17:00no idea
- 1:17:00you you're right you're right i'm i'm
- 1:17:02worried about that too because that's
- 1:17:04that's actually that is the reality in
- 1:17:05many developing countries
- 1:17:07yeah thank you yeah hello thank you yep
- 1:17:11yeah i wanted to take on what my
- 1:17:13colleague just explained now with
- 1:17:14respect to
- 1:17:15uh the valid return of education
- 1:17:17especially
- 1:17:18territory institutions uh i think uh uh
- 1:17:21patronus also spoke on this but it
- 1:17:23should be
- 1:17:25for about the attire has been debunked
- 1:17:27that i can remember in the year 2000
- 1:17:30there was a conference head over there
- 1:17:31during the dental uh
- 1:17:33united nations ahead of kofi anna they
- 1:17:36have a conference i mean summit in
- 1:17:37senegal
- 1:17:39with respect to that of the
- 1:17:41international monetary fund and the
- 1:17:43world bank
- 1:17:44and that of the uh the other sister
- 1:17:46organization the state would give the
- 1:17:47whole
- 1:17:49then they have a conference specifically
- 1:17:51especially in africa most of the
- 1:17:53developing countries they
- 1:17:54they don't invest technically in
- 1:17:56education especially high in
- 1:17:58education like the other second rate and
- 1:18:00and and and other for
- 1:18:02the and other territory institutions
- 1:18:03simply because while they believe that
- 1:18:05they return to education
- 1:18:06it must grow lesser especially for high
- 1:18:08school and uh
- 1:18:10and university or college in college
- 1:18:11education but then
- 1:18:13most often judging from the what have
- 1:18:16been experienced in
- 1:18:17africa especially most of the african
- 1:18:19countries developing countries is that
- 1:18:21they invest most of things in the
- 1:18:22infrastructure development attack of
- 1:18:24social capital where rahima capital are
- 1:18:26left behind
- 1:18:27but in terms of purchasing other
- 1:18:29different mineral research i mean other
- 1:18:31different materials that sort of
- 1:18:32constructions
- 1:18:34and maybe bringing expertise down to
- 1:18:35come and walk to come and educate the
- 1:18:37people over there
- 1:18:38it is much more like great and expensive
- 1:18:40more than that of developing nations
- 1:18:42so if at all quality education has no
- 1:18:44more i mean return in terms of
- 1:18:46investment
- 1:18:47without an investment then technically
- 1:18:48speaking i'm not quite sure that there
- 1:18:50will be an advancement in what's in this
- 1:18:51african conscious because with all the
- 1:18:53progressions of human capital in a
- 1:18:55country it is difficult
- 1:18:56take this as a case study how you expect
- 1:18:58somebody to construct a
- 1:19:00bridge or breaches tonight and other
- 1:19:02different heroes without having the
- 1:19:04expertise
- 1:19:04so without advance knowledge of
- 1:19:06education would be quite more difficult
- 1:19:08so the quality of education is one of
- 1:19:09the major problems that we have in most
- 1:19:11of the african countries
- 1:19:12especially specifically most of the
- 1:19:15african country higher institutions they
- 1:19:17are embedded with political
- 1:19:19i mean infiltrations instead of
- 1:19:21institution to be independent of their
- 1:19:22own
- 1:19:23and crafting uh uh let's just say uh
- 1:19:26institutional policy based on
- 1:19:27state-of-the-art technology or based on
- 1:19:29state or other educations so the major
- 1:19:31problem is the institutions
- 1:19:32so institutional failures are one of the
- 1:19:34major urban problems
- 1:19:36that we have in most of the african
- 1:19:37country thanks
- 1:19:39thank you
- 1:19:42let me try to put two more mechanisms in
- 1:19:46and then i'll stop and take some
- 1:19:47questions i'm sorry i know i'm running a
- 1:19:48little late but i'll stay as late as
- 1:19:49anybody wants to ask me questions
- 1:19:53there's two other ideas that float out
- 1:19:54there one is to let
- 1:19:57another investment matter for human
- 1:19:59capital production
- 1:20:01and one that's been shown to work really
- 1:20:02well this this dates back to manueli and
- 1:20:04sasha
- 1:20:05is to let people buy some sort of goods
- 1:20:07to be used in the production of human
- 1:20:09capital
- 1:20:10and goods here you want to think about
- 1:20:11something that's produced so books
- 1:20:14chalkboards desks computers paper pens
- 1:20:16etc
- 1:20:19if you do that you get a problem that
- 1:20:21looks like this now the budget
- 1:20:23constraint says that
- 1:20:24consumption over my life plus e that's
- 1:20:27my expenditures on the goods
- 1:20:29has to be equal to what i earn and on
- 1:20:32the right hand side the only thing
- 1:20:33that's changed is that my human capital
- 1:20:34depends on how long i spend in school
- 1:20:36and how much i earn
- 1:20:40if you specialize to the power human
- 1:20:42capital production function which in
- 1:20:44practice everybody does
- 1:20:46then you can show very simply i've got
- 1:20:47the derivations in the back i'm not
- 1:20:49going to do them today
- 1:20:50this does not fix the problem but how
- 1:20:52long you go to school
- 1:20:54is the same in all countries but
- 1:20:57people in richer countries or higher tfp
- 1:20:59countries
- 1:21:00will spend more on school and so the way
- 1:21:03the literature thinks about this is that
- 1:21:05that could give you more education
- 1:21:07quality right you have more books
- 1:21:08chalkboards better teachers or something
- 1:21:11like that
- 1:21:12that will give you more expenditures and
- 1:21:14then you can show that we'll also raise
- 1:21:15human capital
- 1:21:17okay so one trick you can do is just to
- 1:21:19say it's not only my time that i
- 1:21:20invest i also have to invest resources
- 1:21:23and the underlying intuition i'm not
- 1:21:24going to have time to go through all the
- 1:21:26math
- 1:21:26the underlying intuition here is simply
- 1:21:29that rich countries
- 1:21:30computers are cheap and so if you can
- 1:21:32use computers to buy education quality
- 1:21:35people in which countries will naturally
- 1:21:36buy more computers and they will get
- 1:21:38more education quality and they'll get
- 1:21:39more human capital
- 1:21:41this is probably the most widely used
- 1:21:43mechanism right now
- 1:21:45if you want a model that gets you
- 1:21:46cross-country human capital differences
- 1:21:48this is sort of what's most commonly
- 1:21:50used at the moment
- 1:21:54the last thing you can do is let the
- 1:21:55government matter
- 1:21:57through something that looks like public
- 1:21:59education and the way the public
- 1:22:01education works is imagine that the
- 1:22:03government also provides an input to
- 1:22:04human capital
- 1:22:06there's many ways to write this down and
- 1:22:08i'm running out of time so i'll just say
- 1:22:09quickly
- 1:22:10the basic idea here is that the
- 1:22:11government can matter either if it
- 1:22:12provides so much resources
- 1:22:14that it's basically you know getting
- 1:22:16families to invest more than they would
- 1:22:18have
- 1:22:18or if the government provides a
- 1:22:20complementary input to human capital
- 1:22:22production
- 1:22:24so there are a smaller set of papers
- 1:22:26that do this
- 1:22:28there are a few other there are a few
- 1:22:30other ideas out there and the one thing
- 1:22:32i want to say before i conclude
- 1:22:33i think the big open thing here most of
- 1:22:36this and most of what i've talked about
- 1:22:38and really most of the human capital
- 1:22:39literature in terms of modeling has been
- 1:22:41aggregate
- 1:22:42and so especially for a group like stag
- 1:22:44i think something that's really
- 1:22:45interesting is that
- 1:22:46these issues of skill bias technical
- 1:22:49change
- 1:22:50where what you the value of your human
- 1:22:53capital depends on the state of
- 1:22:54technology
- 1:22:55or also structural trans structural
- 1:22:58transformation
- 1:22:59right maybe the value of your human
- 1:23:01capital depends on what sectors are
- 1:23:02growing versus shrinking
- 1:23:04right maybe human capital is more
- 1:23:06valuable in a non-agricultural society
- 1:23:08than an agricultural society
- 1:23:09these are ideas that i think still could
- 1:23:11use to be explored more
- 1:23:12these are things that could be built
- 1:23:13into models of human capital across
- 1:23:15countries
- 1:23:17i think basically i should stop there
- 1:23:18i'm way over time as it is and i
- 1:23:20promised i would take questions
- 1:23:21so let me call it a conclusion those are
- 1:23:23the two themes
- 1:23:24somebody else talk
- 1:23:35uh i have a question about probably the
- 1:23:37very last point
- 1:23:38uh on structural change so i i didn't
- 1:23:41see much on the demand side
- 1:23:42uh meaning if there are no for instance
- 1:23:46let's say
- 1:23:47firms large firms like in western
- 1:23:49countries demanding for skills
- 1:23:52um i i see why it would be difficult for
- 1:23:56people in a developing country because
- 1:23:59there's no return to such investment you
- 1:24:02see
- 1:24:02so i wonder whether for this kind of
- 1:24:06models this is something that has been
- 1:24:07implemented if it's more like
- 1:24:09general equilibrium kind of thing
- 1:24:11structural change
- 1:24:13and so on and so forth um
- 1:24:20so i've seen two related ideas this is a
- 1:24:22great question i think it's
- 1:24:23something that's still under explored
- 1:24:25there's two related ideas that float out
- 1:24:27there
- 1:24:29one is you can write down a model where
- 1:24:30skilled and unskilled labor
- 1:24:32are imperfect substitutes like you would
- 1:24:35do in most labor
- 1:24:36models at this point and then you can
- 1:24:39have something that's called skill bias
- 1:24:40technical change right so that that
- 1:24:42benefits the skilled labor relative to
- 1:24:44the unskilled labor
- 1:24:46and then in that model there is an idea
- 1:24:48that whether you want to become skilled
- 1:24:50depends on how much skill bias technical
- 1:24:52change there has been
- 1:24:54and so i could point you to a few papers
- 1:24:55that are thinking about the world that
- 1:24:57way i think that's
- 1:25:00the most fully worked out model that
- 1:25:02i've seen that has these ideas
- 1:25:04a related thing that's out there i think
- 1:25:06many people have known and shown
- 1:25:08empirically that the value of skills
- 1:25:10like the return to a year of schooling
- 1:25:12is much higher in parts of services like
- 1:25:15business services
- 1:25:17there's a really high return to skill
- 1:25:19it's really low in agriculture
- 1:25:22so i think there's probably an interplay
- 1:25:24there which is that as an economy
- 1:25:25experiences structural transformation as
- 1:25:27agriculture shrinks
- 1:25:28and the skilled service sector grows
- 1:25:30there's probably a rising demand
- 1:25:32for for education and that might lead
- 1:25:34workers to get more education
- 1:25:36um joe do you have the full model of
- 1:25:38that would you say i don't know he's
- 1:25:40probably not listening but
- 1:25:41joe has the closest model i've seen to
- 1:25:43that but i don't think he has all of
- 1:25:44that fully worked out i think there's
- 1:25:45still some room for that idea
- 1:25:48yeah i agree that there's room i
- 1:25:51actually there was a
- 1:25:52related question in the q a and i
- 1:25:53answered i think that there's an area
- 1:25:55for research
- 1:25:58yeah i'm i'm really i mean i'm surprised
- 1:26:00i haven't done it i'm surprised nobody's
- 1:26:02done it i'm surprised you haven't done i
- 1:26:03mean
- 1:26:04it's been kind of floating in the work
- 1:26:06but i have not seen anybody fully work
- 1:26:08it out i think it would be great
- 1:26:13thank you very much i mean i don't have
- 1:26:15a full model
- 1:26:16part of my research is about
- 1:26:18liberalization of services
- 1:26:20and how this uh fosters human capital
- 1:26:23accumulation because
- 1:26:25this attracts uh new firms
- 1:26:28uh from foreign firms or private sector
- 1:26:31firms
- 1:26:32and this raises the returns to education
- 1:26:36i mean i've not seen anybody even build
- 1:26:39that in i agree that seems like a
- 1:26:40natural starting point right like we
- 1:26:42know
- 1:26:43you can just go get i've done this you
- 1:26:45can go get minster wage equations and
- 1:26:46just show that schooling is twice as
- 1:26:48valuable in some of the service sectors
- 1:26:50than it is in agriculture
- 1:26:52then it's obvious that i mean that seems
- 1:26:54like something you could just build into
- 1:26:55the model
- 1:26:56pretty easily that at least right that
- 1:26:58as service sectors grow because of
- 1:27:00liberalization structures that's what
- 1:27:01you're talking about right yeah yeah
- 1:27:03that seems like a great
- 1:27:04starting point at least i i hope people
- 1:27:06take these ideas up
- 1:27:09alicia you had a question about degrees
- 1:27:11versus years of school
- 1:27:14yes thank you professor and thank you
- 1:27:17for your lecture i have a question
- 1:27:19and in the first approach we treat the
- 1:27:22workers with and without a degree
- 1:27:24basically the same but in real life with
- 1:27:27like
- 1:27:28because firms only if
- 1:27:31some workers with certain degree or
- 1:27:34higher
- 1:27:35which could cause their wage differences
- 1:27:37and their
- 1:27:38human capital accumulation in the future
- 1:27:40so i think like the
- 1:27:42degree might matters in in a way i'm
- 1:27:46wondering
- 1:27:47do we have evidence in literature shows
- 1:27:50that
- 1:27:51the years of schooling matters more than
- 1:27:53the
- 1:27:54certain degrees yep great that's a great
- 1:27:57question so
- 1:27:59i'll give you two answers one is if you
- 1:28:01want to just read about this a little
- 1:28:02bit
- 1:28:03it has the weirdest name in the world
- 1:28:04the literature is called the literature
- 1:28:06on sheepskin
- 1:28:07effects i'm so sorry i don't know why
- 1:28:10they decided that was a good idea but if
- 1:28:11you search for the phrase sheepskin
- 1:28:14effects like literally skin of sheep
- 1:28:16you're going to find the papers you're
- 1:28:17looking for
- 1:28:20and that's the literature which asks
- 1:28:22exactly the question you have in mind
- 1:28:24which is
- 1:28:24if i know you went to 16 years of school
- 1:28:27but you didn't complete college versus
- 1:28:29whether you did does that still make a
- 1:28:31difference for your wages and the answer
- 1:28:32is yes
- 1:28:32the answer is it makes a pretty big
- 1:28:34difference and so people have
- 1:28:35investigated that in a wide variety of
- 1:28:37ways
- 1:28:39and then they've talked about whether
- 1:28:40that has something to do with selection
- 1:28:42or signaling there's a whole literature
- 1:28:43which is
- 1:28:45honestly totally different from what i
- 1:28:46talked about today at a practical level
- 1:28:49with people in macro development the
- 1:28:50papers i'm talking about today including
- 1:28:52my own
- 1:28:54really in most countries data sets they
- 1:28:56don't ask how long you went to school
- 1:28:57they ask what degree you have like do
- 1:28:59you have a college degree
- 1:29:00and then what most people including me
- 1:29:02do is we say well college takes 16 years
- 1:29:04and we just write 16 years of schooling
- 1:29:06and then we run the linear wage equation
- 1:29:10okay so the idea that you need a certain
- 1:29:13degree or that this degree is more
- 1:29:15valuable than that one that's just
- 1:29:18ignored that's the that's the that's the
- 1:29:20best phrase i can give you for it
- 1:29:23thank you you're welcome the honest
- 1:29:25truth is
- 1:29:29signaling is really tough for human
- 1:29:30capital people right
- 1:29:33yeah and when i say degree not only
- 1:29:36like the degrees also could be the
- 1:29:40graduate
- 1:29:41high school and the middle school like
- 1:29:44the all matters
- 1:29:45especially for developing countries yeah
- 1:29:48yep
- 1:29:49yep i agree completely and like i said
- 1:29:51it's something that
- 1:29:55i don't think anybody's really taken
- 1:29:57into account yet i've not seen it
- 1:29:59todd there's another great question in
- 1:30:01the q a q a a becker type question from
- 1:30:03emmanuel leclaire when we think about
- 1:30:06borrowing constraints is there also view
- 1:30:08that a firm may not want to invest in
- 1:30:10developing technology
- 1:30:12that supports high skilled individuals
- 1:30:14because human capital is intangible so
- 1:30:16not collateralizable
- 1:30:19and imperfect financial markets may lead
- 1:30:21firms to invest in technology
- 1:30:23that promotes the use of
- 1:30:24collateralizable capital instead
- 1:30:27yep that's a fantastic question um
- 1:30:33you it's such a good question it's tough
- 1:30:37to answer
- 1:30:39my hunch is yes
- 1:30:42really when we think about these issues
- 1:30:47you know this is this is
- 1:30:50all right let me talk away from the
- 1:30:51literature now let's throw the
- 1:30:52literature away for a minute and i'll
- 1:30:53come back in a second
- 1:30:55i think most of us would agree that the
- 1:30:58value of
- 1:30:59investing in specific technologies
- 1:31:02plants organizational structures depends
- 1:31:04very much on the types of skills workers
- 1:31:06have
- 1:31:07the types of skills workers are willing
- 1:31:09to get depends on the plant
- 1:31:10organizational structure and technology
- 1:31:12that firms are going to invest in
- 1:31:14they're complements and if either one of
- 1:31:15those is constrained it's going to
- 1:31:17affect both margins that's kind of the
- 1:31:18idea of the question the way i would see
- 1:31:20it i think that's exactly right
- 1:31:23ben jones has a paper where he kind of
- 1:31:25like talks about this stuff
- 1:31:27i don't think he has a full quantitative
- 1:31:29model of it though he kind of
- 1:31:31hints at it i don't think anybody's
- 1:31:34really worked it out
- 1:31:37now coming back to the literature you'll
- 1:31:40notice my answer to a lot of these
- 1:31:41things are the same
- 1:31:43a lot of the really best questions come
- 1:31:45back to the same thing which is
- 1:31:49here once you write down this production
- 1:31:52function that stuff can't show up
- 1:31:55so what would be really interesting if
- 1:31:57you wanted to do that i can kind of give
- 1:31:58you a road map of how to do it you would
- 1:32:00want to write down again the model where
- 1:32:02skilled and unskilled labor are like two
- 1:32:03distinct types
- 1:32:05and they're imperfect substitutes then
- 1:32:07you want to have skill bias technical
- 1:32:09change but you want firms to invest in
- 1:32:11that and you want the workers to invest
- 1:32:12in the skills
- 1:32:14and then you constrain one of them with
- 1:32:16a borrowing constraint that's a model
- 1:32:17where you could talk about all of this
- 1:32:19you'll notice that's not this model this
- 1:32:20model would not even let you begin to
- 1:32:22have that conversation
- 1:32:23so i think that's a fantastic idea that
- 1:32:25would be really interesting to read
- 1:32:30okay unfortunately we are um out of time
- 1:32:34and um todd is willing to stay here but
- 1:32:37i know uh
- 1:32:38mandy and kirsty uh it's late in the
- 1:32:40evening for them over in the uk
- 1:32:42um so i want to thank todd i want to
- 1:32:45thank you all for participating
- 1:32:47um again the todd's talk and his slides
- 1:32:50are available on the stegg website
- 1:32:53and tomorrow uh 4 p.m london time we
- 1:32:56have bertolt herrendorf who will start
- 1:32:58talking about
- 1:32:58um structural transformation at the
- 1:33:01level of sectors
- 1:33:02um so let's uh let's i've already done
- 1:33:06it thank you
- 1:33:07very much todd and uh we'll see you all
- 1:33:09tomorrow hopefully
- 1:33:10thank you bye-bye um hello todd
- 1:33:14hi yeah uh there is an interesting thank
- 1:33:17you very
- 1:33:18much for the lecture it's quite
- 1:33:21inspiring uh there's an interesting
- 1:33:23perspective here in
- 1:33:24in germany uh they they have
- 1:33:27well structured um
- 1:33:31uh how do i put it now a kind of labor
- 1:33:35labor market kind of um the
- 1:33:38the year of schooling is structured in
- 1:33:40such a way that when
- 1:33:42a child gets to a particular level it
- 1:33:44can choose to
- 1:33:45whether move for a degree or to go for
- 1:33:48what they call a kind of training
- 1:33:49what they call house building and um
- 1:33:53i'm not sure if there's any study on
- 1:33:54these so far but there have been a lot
- 1:33:57of concern with respect to that because
- 1:33:59those who actually go for the house
- 1:34:02bidding system
- 1:34:03they tend to progress faster in their
- 1:34:06career because many of the organizations
- 1:34:07just need
- 1:34:08the only job experience
- 1:34:12you guys know so after like a two or
- 1:34:14three year of training
- 1:34:16you go right on into the organization uh
- 1:34:19if it is a mechanical electrical or
- 1:34:21whatever depending on the industry
- 1:34:23and then you get um on-the-job training
- 1:34:26now
- 1:34:26how do we factor in for this variation
- 1:34:29in in some of this model
- 1:34:30because at the end of the day the guy
- 1:34:33grows on the job
- 1:34:35and we i think they reward more
- 1:34:38on years of experience and and that's
- 1:34:40why i particularly like that model the
- 1:34:43the uh mindsets wage equation because it
- 1:34:46captures both the
- 1:34:48years of schooling and as well as the
- 1:34:58experience
- 1:35:00yes and that's why i think you know
- 1:35:04we were excited to uh reincorporate
- 1:35:06experience back into this
- 1:35:10so at that level you know i think it's
- 1:35:12taken into account and this
- 1:35:13what i mean by that is that if what
- 1:35:16we're interested in is just measuring
- 1:35:17human capital and making sure we
- 1:35:19measure experience yeah into human
- 1:35:22capital
- 1:35:22that i feel good about you know that
- 1:35:24that is captured by by these papers
- 1:35:29there's a second effect which is around
- 1:35:32the world countries structure their
- 1:35:34educational systems very differently
- 1:35:36very differently yeah in some countries
- 1:35:39people they call this tracking
- 1:35:40you know when you start to break
- 1:35:42students into different groups and some
- 1:35:43of them are labeled the college group
- 1:35:44and some are labeled the work group
- 1:35:47some countries do that very early some
- 1:35:49countries do it very late
- 1:35:51some countries set up exams so that
- 1:35:53students study like crazy when they're
- 1:35:5515 years old in america you don't do
- 1:35:56anything when you're 15 years old
- 1:35:58yeah at least i didn't um
- 1:36:03and i don't think anyone has yet figured
- 1:36:05out the importance of those institutions
- 1:36:07you know i'm saying like
- 1:36:08the fact that it affects the experience
- 1:36:10profile we've measured that that's great
- 1:36:12i feel good about that or i don't know
- 1:36:14as good as i do about anything
- 1:36:16um
- 1:36:19but the underlying importance of the
- 1:36:21institutions i don't think we have a
- 1:36:22good handle on that
- 1:36:24that's the truth and if you look by the
- 1:36:26way if you look at
- 1:36:27germany germany is a really weird
- 1:36:29country when you do these calculations
- 1:36:31barrow and lee tell us that germans have
- 1:36:33very low education levels
- 1:36:35because people aren't in schooling very
- 1:36:37long they go into these vocational
- 1:36:38training
- 1:36:39i can't say the german word house
- 1:36:41whatever yeah
- 1:36:43but then if you look at their experience
- 1:36:44profiles they're extremely steep germany
- 1:36:46has the steepest experience profiles of
- 1:36:48any country in the world
- 1:36:50so they're a very unusual country in
- 1:36:52this sense right very little education
- 1:36:54and education human capital but more
- 1:36:55experienced human capital
- 1:36:57it would be nice to have a theory of
- 1:36:58that but i don't think anyone does
- 1:37:00yeah absolutely and i think so to a very
- 1:37:02large extent
- 1:37:03maybe and i saw one of the graphs you
- 1:37:06you
- 1:37:07presented where the return on education
- 1:37:10is actually higher
- 1:37:11even than that of america that of us and
- 1:37:14all of that and
- 1:37:15and i i think it's also partly because
- 1:37:17they have this graded
- 1:37:19returns definitely if you have a
- 1:37:22bachelor's degree you don't have the
- 1:37:24same amount as someone who has a
- 1:37:26master's degree
- 1:37:28and then if you have a phd so they've
- 1:37:30got this graded
- 1:37:31system that that is actually uh used in
- 1:37:34in in in how they uh calculate
- 1:37:37their thing but i don't know and but
- 1:37:41for you which do you think is the best
- 1:37:43model
- 1:37:44for a developing country to approach you
- 1:37:46know
- 1:37:47uh adopt for example
- 1:37:50i think the truth is that there is so
- 1:37:52little research that's been done on this
- 1:37:54that i don't even know where to start
- 1:37:57okay i'm somebody who's really reluctant
- 1:37:59to make policy prescriptions
- 1:38:01you know even in cases where i think
- 1:38:02there's been a lot of work done but here
- 1:38:04there's been almost no work i
- 1:38:07like i wouldn't even know what paper to
- 1:38:09recommend to you to read so that you
- 1:38:11could start
- 1:38:12this is this is this is totally
- 1:38:13uncharted area as far as i know
- 1:38:15i think this is probably sorry i think
- 1:38:18this is probably a moment
- 1:38:19to make clear the distinction between
- 1:38:21the academic research
- 1:38:22and the policy conversation which is
- 1:38:25important
- 1:38:26and which we hope to inform but where
- 1:38:30the decisions that get made are often
- 1:38:33um are often based on much more than the
- 1:38:36academic evidence
- 1:38:37right political political forces come to
- 1:38:39bear
- 1:38:41it's not clear that the policy choices
- 1:38:44should be made entirely based on
- 1:38:46on what the academic evidence suggests
- 1:38:51because political processes are there
- 1:38:53for a reason
- 1:38:54but i think it's a really important and
- 1:38:56interesting set of questions that you
- 1:38:57raise about what policy should do
- 1:38:59i'd love to continue that conversation
- 1:39:01but i i am conscious that here in
- 1:39:04in the uk as in other places we're
- 1:39:06keeping our colleagues at cepr
- 1:39:09um past the end of their work day and i
- 1:39:12think we should
- 1:39:13wind things up i want to thank i want to
- 1:39:16thank
- 1:39:16todd i also want to thank the members of
- 1:39:19the panel the
- 1:39:20participants who've been here um you've
- 1:39:22all done just a fantastic job it's great
- 1:39:24to have these conversations
- 1:39:26and um and i think
- 1:39:30one of the things we need to reflect on
- 1:39:32collectively is this
- 1:39:33relationship between what we do as
- 1:39:35researchers what we do as academic
- 1:39:37economists
- 1:39:38and and the real deep challenges of
- 1:39:42making policy
- 1:39:43um one of the things that the stag
- 1:39:46program is supposed to do
- 1:39:47is to support research that speaks to
- 1:39:50policy
- 1:39:51and we've all to be very honest we all
- 1:39:53struggle with what that means
- 1:39:54i think many of us like todd um feel
- 1:39:57very uncomfortable
- 1:39:59with the awareness that what we have to
- 1:40:01say is only
- 1:40:03only begins to get to the edges of the
- 1:40:06big policy questions
- 1:40:07and i think what what you've raised are
- 1:40:11abdullahi are really the central
- 1:40:13questions that policymakers struggle
- 1:40:14with
- 1:40:15how should we design our systems in any
- 1:40:18event
- 1:40:18i'd like to thank those of us who are
- 1:40:20still around i would encourage you if
- 1:40:22you can to unmute your
- 1:40:23your microphones and let's give todd an
- 1:40:25actual um
- 1:40:27old-fashioned out loud round of applause
- 1:40:30um
- 1:40:31i just think we want to thank you for
- 1:40:32taking the time out of your day and for
- 1:40:34the effort that went into preparing the
- 1:40:36lecture todd um we'll see you all
- 1:40:38tomorrow tomorrow
- 1:40:41todd thanks thanks a ton thank you for
- 1:40:44the opportunity thanks for that
- 1:40:46thanks a lot bye everybody bye
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