曼昆《经济学原理》习题答案（第十二章）
2010-04-12 13:27阅读：
Questions for Review：
1. What does the level of a nation’s GDP measure? What
does the growth rate of GDP measure? Would you
rather live in a nation with a high level of GDP and a
low growth rate, or in a nation with a low level and a
high growth rate?
答案：an economy’s gross domestic product(GDP) measures both the total
income earned in the economy and the total expenditure on the
economy’s output of goods and services. The level of real GDP is a
good gauge of economic prosperity, and the growth of real GDP is a
good gauge of
economic progress.I'd rather live in a nation with high level of
GDP and a low growth rate because high level of GDP is a kind of
guarantee of relatively high level of living standard.
2. List and describe four determinants of productivity.
答案：physical capital, human capital, natural resources, and
technological knowledge available to workers.
3. In what w
ay is a college degree a form of capital?
答案：Human capital is the economist’s term for the knowledge and
skills that workers acquire through education, training, and
experience.Like physical capital, human capital raises a nation’s
ability to produce goods and services. Also like physical capital,
human capital is a produced factor of production.Producing human
capital requires inputs in the form of teachers, libraries,
and student time. Indeed, college students can be viewed as
“workers” who have the important
job of producing the human capital that will be used in future
production.
4. Explain how higher saving leads to a higher standard of
living. What might deter a policymaker from trying to
raise the rate of saving?
答案：Because capital is a produced factor of production, a society
can change the amount of capital it has. If today the economy
produces a large quantity of new capital goods, then tomorrow it
will have a larger stock of capital and be able to produce more of
all types of goods and services. Thus, one way to raise future
productivity is to invest more current resources in the production
of capital.But for society to invest more in capital, it must
consume less and save more of its current income. The growth that
arises from capital accumulation is not a free lunch: It requires
that society sacrifice consumption of goods and services in the
present in order to enjoy higher consumption in the future, which
might deter a policymaker from trying to raise the
rate of saving.
5. Does a higher rate of saving lead to higher growth
temporarily or indefinitely?
答案：The traditional view of the production process is that capital
is subject to diminishing returns: As the stock of capital rises,
the extra output produced from an additional unit of capital
falls.Because of diminishing returns, an increase in the saving
rate leads to higher growth only for a while.So higher rate of
saving lead to higher growth temporarily.
6. Why would removing a trade restriction, such as a tariff,
lead to more rapid economic growth?
答案：Most economists today believe that poor countries are better off
pursuing outward-oriented policies that integrate these countries
into the world economy. Chapters 3 and 9 showed how international
trade can improve the economic wellbeing of a country’s citizens.
Trade is, in some ways, a type of technology.A country that
eliminates trade restrictions will, therefore, experience the same
kind of economic growth that would occur after a major
technological advance.
7. How does the rate of population growth influence the
level of GDP per person?
答案：Standard theories of economic growth predict that high
population growth reduces GDP per person. The reason is that rapid
growth in the number of workers forces the other factors of
production to be spread more thinly.In particular,when population
growth is rapid, equipping each worker with a large quantity of
capital is more difficult. A smaller quantity of capital per worker
leads to lower productivity and lower GDP per worker.
8. Describe two ways in which the U.S. government tries
to encourage advances in technological knowledge.
答案：The government continues to encourage advances in knowledge with
research grants from the National Science Foundation and the
National Institutes of Health and with tax breaks for firms
engaging in research and development.Yet another way in which
government policy encourages research is through the patent
system.
Problems and Applications：
1. Most countries, including the United States, import
substantial amounts of goods and services from other
countries. Yet the chapter says that a nation can enjoy a
high standard of living only if it can produce a large
quantity of goods and services itself. Can you reconcile
these two facts?
答案：Trade is, in some ways, a type of technology.A country that
eliminates trade restrictions will, therefore, experience the same
kind of economic growth that would occur after a major
technological advance.Without being able to take advantage of the
gains from trade, a country would need to produce all
the goods it consumes.It would also have to produce all its own
capital goods, rather than importing state-of-the-art equipment
from other cities. Living standards in that country would fall
immediately, and the problem would likely only get worse over
time.So trade will improve a country's productivity and thus make
the nation enjoy high standard of living.
2. List the capital inputs necessary to produce each of the
following:
a. cars
b. high school educations
c. plane travel
d. fruits and vegetables
答案：physical capital, human capital, natural resources, and
technological knowledge are four determinants of productivity, all
of which are the capital input needed for production.
I will answer this question according to these four elements
of productivity.
a. workshop & work tools; skilled workers; land,
water& steel; assembly lines & management
systems;
b. classroom; teachers; campus;textbook;
c. plane; pilot & Stewardess; airport; air trafic control
system & communication system.
d. tools & fertilizer; farmer; land, water & seed;
agricultural technology;
3. U.S. income per person today is roughly eight times
what it was a century ago. Many other countries have
also experienced significant growth over that period.
What are some specific ways in which your standard of
living differs from that of your great-grandparents?
答案：Our standard of living differs in many ways from that of my
great-grandparents.Firstly we enjoy sufficient food supply and have
more than enough clothes;Secondly we have improved
social welfare system like medical, education,
transportation and other infrastructure; thirdly we
benefit from advanced technology which my
great-grandparents could never dream of. Despite all these
above mentioned benefits we now have a
deteriorated environment and can not enjoy the
fresh air, clear water and cool breeze brought by the tree
shadow which my great-grandparents took for granted.
4. The chapter discusses how employment has declined
relative to output in the farm sector. Can you think of
another sector of the economy where the same
phenomenon has occurred more recently? Would you
consider the change in employment in this sector to
represent a success or a failure from the standpoint of
society as a whole?
答案：(未完待续）
5. Suppose that society decided to reduce consumption
and increase investment.
a. How would this change affect economic growth?
b. What groups in society would benefit from this
change? What groups might be hurt?
答案：Because resources are scarce, devoting more resources to
producing capital requires devoting fewer resources to producing
goods and services for current consumption. That is, for society to
invest more in capital, it must consume less and save more of its
current income. The growth that arises from capital accumulation is
not a free lunch: It requires that society sacrifice consumption of
goods and services in the present in order to enjoy higher
consumption in the future.
a. Because capital accumulation affects productivity so clearly and
directly, many economists believe that high investment leads
to more rapid economic growth.
b. Because to reduce consumption and increase investment requires
that society sacrifice consumption of goods and services in the
present in order to enjoy higher consumption in the future. So the
younger generation will benefit from this change and the current
generation will do the sacrifice. Like in China, 30 years ago when
my parents were working hard with only RMB 30-40 per month and
limited goods and service for consumption and now in return
we younger generation can enjoy much higher living standard and
consumption.
