ECO 335 EXAM 2

What is human capital?

Human capital is the set of qualities of labor that make workers more productive. Economists especially focus on qualities that are produced by investment, similar to physical capital.

What are the two main forms of human capital emphasized in this lecture?

Health and education.

Why does human capital matter for economic growth?

Because differences in human capital help explain differences in productivity and income across countries.

How is human capital similar to physical capital?

Both are produced through investment, both raise productivity, and both depreciate over time.

How is human capital different from physical capital?

Human capital is embodied in people rather than machines or structures.

What happens to labor productivity when human capital rises?

Labor becomes more productive, so the marginal product of labor rises.

What is the return to human capital?

The return to human capital is the increase in wages to the worker who owns it, since wages reflect the marginal product of labor.

Why is health considered a form of human capital?

Because healthier people can work harder, work longer, and think more clearly, which raises productivity.

What is the basic relationship between health and income?

Better health raises income by raising productivity, and higher income improves health through better nutrition, care, and living conditions.

Why can health and income create multiplier effects?

Because income improves health, then better health raises income further, reinforcing the original effect.

What does the “How Health Interacts with Income” graph show?

It shows a two-way relationship: health affects income and income affects health, so equilibrium reflects both forces working together.

What does the “Effect of an Exogenous Change in Income” graph show?

It shows that an outside increase in income raises health, and the resulting better health then raises income again, creating a multiplier effect.

Why do richer countries often have better nutrition?

Higher income allows greater access to calories and better food, which improves worker health and productivity.

Why do richer countries often have higher life expectancy?

Higher income is associated with better living conditions, health care, and nutrition, all of which improve survival and productivity.

Why is education considered human capital?

Because education builds productive skills and knowledge that raise worker productivity and earnings.

Why is education especially important in more developed economies?

Because intellectual ability becomes more important relative to physical ability in determining wages.

Why can education be especially costly in countries with rapid population growth?

Because a large fraction of the population is school-age, so educating everyone requires large resources.

What are the benefits of additional schooling?

Higher productivity, higher wages, and greater lifetime earnings.

What are the direct costs of schooling?

Tuition, books, fees, transportation, and other school-related expenses.

What are the indirect costs of schooling?

Forgone earnings from not working while in school.

What is the basic tradeoff in choosing more schooling?

You give up current earnings and pay direct costs now in exchange for higher earnings later.

What does the “Trade-off in the decision to continue schooling” graph show?

It shows that continuing school has direct and indirect costs early on, but later generates benefits through higher earnings.

Are returns to education the same for every additional year of schooling?

No. The lecture shows that returns are not constant across years of schooling.

What pattern does the return-to-education graph show?

Returns are highest in earlier years of schooling and lower in later years; the lecture labels about 13.4%, then 10.1%, then 6.8%.

What is one likely interpretation of declining returns to extra schooling years?

The first years of education may raise productivity more sharply, while later years still help but with smaller marginal gains.

What does the age-earnings profile graph show by education level?

People with more education tend to earn more over the life cycle.

What directly related development issues are mentioned with education returns?

Child labor and the gender gap in education and health.

Why do economists extend the Solow model to include human capital?

Because labor quality differs across economies, and including human capital improves the fit between the model and actual income differences.

In the human-capital extension, what does u represent?

The fraction of an individual’s time spent learning skills instead of working.

In the human-capital extension, what does higher u do?

It means more time is spent accumulating skills, which raises human capital and long-run output per worker.

What is the broad takeaway from the human-capital Solow extension?

Countries are richer not just because of physical capital and technology, but also because they devote more time and resources to skill accumulation.

What are the four reasons listed for why some countries are rich and others poor in this lecture?

High physical-capital investment, low population growth, high levels of technology, and a large fraction of time spent accumulating skills.

What does human capital add to growth accounting?

It lets us explain more of output differences through factor accumulation, reducing how much is left unexplained as pure productivity differences.

What is the difference between output differences due to factor accumulation and due to productivity?

Factor accumulation means countries differ because they have more physical or human capital per worker. Productivity differences mean the same inputs produce different outputs.

What does the “Sources of Differences in Output per Worker” figure teach?

It shows that country output gaps may come from factor accumulation alone, productivity alone, or both together.

If two countries have the same factor accumulation but different output, what does that suggest?

A productivity difference.

If two countries have the same output but one has more factor accumulation, what does that suggest?

The country with more factors likely has lower productivity.

In the L6 worked example, why is A1/A2 = 2 important?

It shows how to infer relative productivity after controlling for differences in physical and human capital.

Why is human capital related to raw labor rather than replacing it entirely?

Because raw labor is the basic labor endowment, while human capital measures the productivity-enhancing quality attached to that labor.

What is the one-sentence summary of L6?

Human capital, especially health and education, raises productivity and wages, helps explain cross-country income differences, and improves growth accounting when added to the Solow framework.

What is the limitation of the Solow model emphasized at the start of L7?

Technology level A is central, but it is exogenous, so the model does not explain technological change or sustained growth.

What was Romer’s main contribution to growth theory?

He distinguished ideas from ordinary goods and treated technological progress as something that can be explained economically rather than treated as manna from heaven.

In Romer’s framework, what are objects?

Ordinary economic goods like labor and capital that are used up or rival in use.

In Romer’s framework, what are ideas?

Instructions, designs, and blueprints for making objects or more ideas.

Why is the distinction between objects and ideas important?

Because objects are rivalrous while ideas are non-rivalrous, and that changes the logic of production, pricing, and growth.

What does rivalrous mean?

One person’s use or consumption of the good reduces another person’s ability to use or consume it.

What does non-rivalrous mean?

One person’s use of the good does not reduce the amount available for others to use.

Why are ideas non-rivalrous?

Once an idea exists, many people can use it at the same time without using it up.

What does excludable mean?

Access to the good can be restricted so that others can be prevented from using it.

What does non-excludable mean?

It is difficult or impossible to prevent others from using the good.

Why is excludability often a legal issue rather than an intrinsic property?

Because societies can create or weaken it through rules like patents, copyrights, and property rights.

What are the four types of economic goods in the rivalry-excludability matrix?

Private goods, common resources, public goods, and artificially scarce goods.

What is a private good?

Rival and excludable.

What is a common resource?

Rival but non-excludable.

What is a public good?

Non-rival and non-excludable.

What is an artificially scarce good?

Non-rival but excludable, often because legal or technical restrictions make access limited.

Why can software be treated as an artificially scarce good?

Because software is non-rival in use, but access can be restricted through licensing or intellectual property.

Why do ideas create fixed costs?

Because developing the idea requires an up-front cost for discovery, design, or R&D before production can scale up.

Why can the combination of ideas and object production create increasing returns to scale?

Because once the fixed cost of the idea is paid, producing more units spreads that cost over more output.

What is the vaccine/antibiotic example meant to illustrate?

There is a large fixed R&D cost to create the formula or idea, after which producing extra units is much easier, leading to increasing returns overall.

What does the fixed-cost graph show?

Without fixed cost, output scales linearly, but with a large fixed cost, average productivity rises as output expands.

Why does average cost stay above marginal cost under increasing returns from fixed cost?

Because marginal cost ignores the sunk fixed cost, while average cost includes spreading that fixed cost over all units.

Why is pricing at P = MC a problem under increasing returns?

Because firms would not recover the fixed research cost, so no producer would earn profit or want to produce.

What is the basic rationale for patents and copyrights in this lecture?

They allow firms to charge above marginal cost so they can recoup fixed R&D costs.

Why does this lecture say imperfect competition may be necessary?

Because with increasing returns from ideas, producers need some market power to cover fixed costs.

What policy issue appears once we allow market power to reward innovation?

Too much market power can be socially costly and may even reduce later innovation, so there is a tradeoff.

What kinds of policy questions arise around intellectual property according to the lecture?

Whether public contributions to private research should affect pricing, whether social benefits matter, and whether excessive market power can harm innovation and growth.

What are common metrics used for the production or use of ideas in the lecture?

Number of researchers, research spending, and patents.

Are researchers and research spending perfect measures of technological activity?

No. They measure effort and inputs, but not necessarily the actual value or quality of innovation.

Are patents a perfect measure of technological activity?

No. Not all innovation is patented, industries vary in patenting, and patents can reflect legal strategy rather than real technological importance.

Why do industries vary in how likely inventions are to be patented?

Because some industries rely more on secrecy, lead time, branding, or complementary capabilities instead of patents.

What are two key legal standards or issues in patenting mentioned in L7?

Whether an invention is novel and nonobvious, and who should receive the patent.

What is the difference between “first to file” and “first to invent”?

First to file gives rights to the earliest patent filer; first to invent gives rights to the original inventor if that can be established.

What big patent-system tradeoff does L7 emphasize?

Encouraging new R&D while not holding back the progress of other firms.

What is the one-sentence summary of L7?

Ideas are non-rival goods that create fixed costs and increasing returns, which explains why innovation, pricing, patents, and market power matter for growth.

What is the main claim of Boldrin and Levine’s Against Intellectual Monopoly as summarized by Gilbert?

They argue patents and copyrights are not necessary for innovation or creative expression and should be eliminated.

Does Gilbert fully agree with abolishing intellectual property?

No. He agrees the system has serious flaws, but argues the case for abolishing all IP is too strong and not supported by the evidence.

What is one major cost of patents according to Gilbert?

They restrict competition, raise prices, lower use, and can create deadweight loss.

Why can patents slow future innovation?

Because innovation is cumulative, so making existing ideas more costly or less accessible can hinder later discoveries.

Why is cumulative innovation so important in the patent debate?

New inventions often build on previous inventions, so today’s IP can become tomorrow’s barrier.

What evidence does Gilbert mention suggesting patents can restrict access to innovation?

He notes cases where innovation sped up after key patents expired or after compulsory licensing expanded access.

What are alternative appropriation mechanisms besides patents mentioned in the reading?

First-mover advantage, secrecy, complementary manufacturing capability, and complementary sales or service capability.

What does the reading say about whether patents are equally important in all industries?

They are not. Their importance varies widely across industries.

In which sectors does Gilbert say patents appear especially important?

Pharmaceuticals, biotech, medical devices, and some startup-heavy sectors.

Why might patents matter especially in pharmaceuticals?

Because drug development requires large up-front R&D investments and products may be relatively easy to copy once discovered.

What is one potential benefit of patents besides rewarding invention directly?

They may encourage disclosure of knowledge rather than secrecy, which can help later innovation.

What is one problem Gilbert identifies with the U.S. patent system?

Patent quality is often poor, and some patents are vague, overbroad, or strategically used.

Why can software and business-method patents be especially problematic according to the reading?

Claims can be fuzzy, novelty is harder to judge, and patent scope may extend beyond what the inventor clearly anticipated.

What does the reading suggest about independent invention?

It appears to be common, which raises doubts about whether lengthy patent protection is always socially desirable.

What is Gilbert’s broad policy conclusion?

The right goal is more likely reforming and rebalancing intellectual property rather than abolishing it entirely.

What is the simplest exam-ready summary of the reading?

Boldrin and Levine argue for abolition; Gilbert says patents have serious costs and need reform, but the evidence does not justify eliminating all intellectual property.

What is the Romer model trying to explain?

The economic forces behind technological progress and sustained growth.

Why is the Romer model called endogenous growth theory?

Because growth and technological progress are outcomes generated inside the model rather than imposed from outside.

For what kind of economies is the Romer model mainly appropriate?

Advanced economies, or the world frontier as a whole, where innovation pushes the technological frontier outward.

What are the two production functions in the simplified Romer model?

One produces output using ideas and labor, and the other produces new ideas using existing ideas and research labor.

What is the output equation in the simplified Romer model?

Y_t = A_t L_Yt.

What does the output equation Y_t = A_t L_Yt mean in words?

Output depends on the stock of ideas and the amount of labor allocated to producing output.

What is the idea-production equation in the simplified Romer model?

ΔA_(t+1) = z A_t L_At.

What does ΔA_(t+1) = z A_t L_At mean in words?

New ideas depend on research labor and on the existing stock of ideas, so ideas help create more ideas.

What does z represent in the Romer model?

A productivity parameter in idea production.