曼昆经济学原理微观经济学英文版
课后习题答案（考试章节筛选）
UNIT 1
SOLUTIONS TO TEXT PROBLEMS:
Quick Quizzes
1. The four principles of economic decisionmaking are: (1) people face tradeoffs; (2)
the cost of something is what you give up to get it; (3) rational people think at the
margin; and (4) people respond to incentives. People face tradeoffs because to get
one thing that they like, they usually have to give up another thing that they like.
The cost of something is what you give up to get it, not just in terms of monetary
costs but all opportunity costs. Rational people think at the margin by taking an action
if and only if the marginal benefits exceed the marginal costs. People respond to
incentives because as they compare benefits to costs, a change in incentives may
cause their behavior to change.
2. The three principles concerning economic interactions are: (1) trade can make
everyone better off; (2) markets are usually a good way to organize economic activity;
and (3) governments can sometimes improve market outcomes. Trade can make
everyone better off because it allows countries to specialize in what they do best and
to enjoy a wider variety of goods and services. Markets are usually a good way to
organize economic activity because the invisible hand leads markets to desirable
outcomes. Governments can sometimes improve market outcomes because
sometimes markets fail to allocate resources efficiently because of an externality or
market power.
3. The three principles that describe how the economy as a whole works are: (1) a
country’s standard of living depends on its ability to produce goods and services; (2)
prices rise when the government prints too much money; and (3) society faces a
short-run tradeoff between inflation and unemployment. A country’s standard of
living depends on its ability to produce goods and services, which in turn depends on
its productivity, which is a function of the education of workers and the access
workers have to the necessary tools and technology. Prices rise when the
government prints too much money because more money in circulation reduces the
value of money, causing inflation. Society faces a short-run tradeoff between
inflation and unemployment that is only temporary and policymakers have some
ability to exploit this relationship using various policy instruments.
Questions for Review
1. Examples of tradeoffs include time tradeoffs (such as studying one subject over
another, or studying at all compared to engaging in social activities) and spending
tradeoffs (such as whether to use your last ten dollars on pizza or on a study guide for
that tough economics course).
2. The opportunity cost of seeing a movie includes the monetary cost of admission plus
the time cost of going to the theater and attending the show. The time cost depends on what else you might do with that time; if it's staying home and watching TV, the
time cost may be small, but if it's working an extra three hours at your job, the time
cost is the money you could have earned.
3. The marginal benefit of a glass of water depends on your circumstances. If you've
just run a marathon, or you've been walking in the desert sun for three hours, the
marginal benefit is very high. But if you've been drinking a lot of liquids recently, the marginal benefit is quite low. The point is that even the necessities of life, like water, don't always have large marginal benefits.
4. Policymakers need to think about incentives so they can understand how people will
respond to the policies they put in place. The text's example of seat belts shows that policy actions can have quite unintended consequences. If incentives matter a lot,
they may lead to a very different type of policy; for example, some economists have
suggested putting knives in steering columns so that people will drive much more
carefully! While this suggestion is silly, it highlights the importance of incentives.
5. Trade among countries isn't a game with some losers and some winners because
trade can make everyone better off. By allowing specialization, trade between
people and trade between countries can improve everyone's welfare.
6. The "invisible hand" of the marketplace represents the idea that even though
individuals and firms are all acting in their own self-interest, prices and the
marketplace guide them to do what is good for society as a whole.
7. The two main causes of market failure are externalities and market power. An
externality is the impact of one person’s actions on the well-being of a bystander,
such as from pollution or the creation of knowledge. Market power refers to the
ability of a single person (or small group of people) to unduly influence market prices, such as in a town with only one well or only one cable television company. In
addition, a market economy also leads to an unequal distribution of income.
8. Productivity is important because a country's standard of living depends on its ability
to produce goods and services. The greater a country's productivity (the amount of goods and services produced from each hour of a worker's time), the greater will be
its standard of living.
9. Inflation is an increase in the overall level of prices in the economy. Inflation is
caused by increases in the quantity of a nation's money.
10. Inflation and unemployment are negatively related in the short run. Reducing
inflation entails costs to society in the form of higher unemployment in the short run. Problems and Applications
1. a. A family deciding whether to buy a new car faces a tradeoff between the
cost of the car and other things they might want to buy. For example,
buying the car might mean they must give up going on vacation for the next
two years. So the real cost of the car is the family's opportunity cost in
terms of what they must give up.
b. For a member of Congress deciding whether to increase spending on
national parks, the tradeoff is between parks and other spending items or
tax cuts. If more money goes into the park system, that may mean less
spending on national defense or on the police force. Or, instead of
spending more money on the park system, taxes could be reduced.
c. When a company president decides whether to open a new factory, the
decision is based on whether the new factory will increase the firm's profits
compared to other alternatives. For example, the company could upgrade
existing equipment or expand existing factories. The bottom line is: Which
method of expanding production will increase profit the most?
d. In deciding how much to prepare for class, a professor faces a tradeoff
between the value of improving the quality of the lecture compared to other
things she could do with her time, such as working on additional research.
2. When the benefits of something are psychological, such as going on a vacation, it isn't
easy to compare benefits to costs to determine if it's worth doing. But there are two ways to think about the benefits. One is to compare the vacation with what you
would do in its place. If you didn't go on vacation, would you buy something like a
new set of golf clubs? Then you can decide if you'd rather have the new clubs or the vacation. A second way is to think about how much work you had to do to earn the money to pay for the vacation; then you can decide if the psychological benefits of the vacation were worth the psychological cost of working.
3. If you are thinking of going skiing instead of working at your part-time job, the cost of
skiing includes its monetary and time costs, which includes the opportunity cost of the wages you are giving up by not working. If the choice is between skiing and going to the library to study, then the cost of skiing is its monetary and time costs including the cost to you of getting a lower grade in your course.
4. If you spend $100 now instead of saving it for a year and earning 5 percent interest,
you are giving up the opportunity to spend $105 a year from now. The idea that
money has a time value is the basis for the field of finance, the subfield of economics that has to do with prices of financial instruments like stocks and bonds.
5. The fact that you've already sunk $5 million isn't relevant to your decision anymore,
since that money is gone. What matters now is the chance to earn profits at the
margin. If you spend another $1 million and can generate sales of $3 million, you'll earn $2 million in marginal profit, so you should do so. You are right to think that the project has lost a total of $3 million ($6 million in costs and only $3 million in revenue) and you shouldn't have started it. That's true, but if you don't spend the additional
$1 million, you won't have any sales and your losses will be $5 million. So what
matters is not the total profit, but the profit you can earn at the margin. In fact,
you'd pay up to $3 million to complete development; any more than that, and you
won't be increasing profit at the margin.
6. Harry suggests looking at whether productivity would rise or fall. Productivity is
certainly important, since the more productive workers are, the lower the cost per
gallon of potion. Ron wants to look at average cost. But both Harry and Ron are
missing the other side of the equation?revenue. A firm wants to maximize its
profits, so it needs to examine both costs and revenues. Thus, Hermione is
right?it’s best to examine whether the extra revenue would excee d the extra costs.
Hermione is the only one who is thinking at the margin.
7. a. The provision of Social Security benefits lowers an individual’s incentive to
save for retirement. The benefits provide some level of income to the
individual when he or she retires. This means that the individual is not
entirely dependent on savings to support consumption through the years in
retirement.
b. Since a person gets fewer after-tax Social Security benefits the greater is his
or her earnings, there is an incentive not to work (or not work as much) after
age 65. The more you work, the lower your after-tax Social Security
benefits will be. Thus the taxation of Social Security benefits discourages
work effort after age 65.
8. a. When welfare recipients who are able to work have their benefits cut off
after two years, they have greater incentive to find jobs than if their benefits
were to last forever.
b. The loss of benefits means that someone who can't find a job will get no
income at all, so the distribution of income will become less equal. But the
economy will be more efficient, since welfare recipients have a greater
incentive to find jobs. Thus the change in the law is one that increases
efficiency but reduces equity.
9. By specializing in each task, you and your roommate can finish the chores more
quickly. If you divided each task equally, it would take you more time to cook than it would take your roommate, and it would take him more time to clean than it would
take you. By specializing, you reduce the total time spent on chores.
Similarly, countries can specialize and trade, making both better off. For example,
suppose it takes Spanish workers less time to make clothes than French workers, and French workers can make wine more efficiently than Spanish workers. Then Spain
and France can both benefit if Spanish workers produce all the clothes and French
workers produce all the wine, and they exchange some wine for some clothes.
10. a. Being a central planner is tough! To produce the right number of CDs by
the right artists and deliver them to the right people requires an enormous
amount of information. You need to know about production techniques
and costs in the CD industry. You need to know each person's musical
tastes and which artists they want to hear. If you make the wrong
decisions, you'll be producing too many CDs by artists that people don't want
to hear, and not enough by others.
b. Your decisions about how many CDs to produce carry over to other decisions.
You have to make the right number of CD players for people to use. If you
make too many CDs and not enough cassette tapes, people with cassette
players will be stuck with CDs they can't play. The probability of making
mistakes is very high. You will also be faced with tough choices about the
music industry compared to other parts of the economy. If you produce
more sports equipment, you'll have fewer resources for making CDs. So all
decisions about the economy influence your decisions about CD production.
11. a. Efficiency: The market failure comes from the monopoly by the cable TV
firm.
b. Equity
c. Efficiency: An externality arises because secondhand smoke harms
nonsmokers.
d. Efficiency: The market failure occurs because of Standard Oil's monopoly
power.
e. Equity
f. Efficiency: There is an externality because of accidents caused by drunk
drivers.
12. a. If everyone were guaranteed the best health care possible, much more of
our nation's output would be devoted to medical care than is now the case.
Would that be efficient? If you think that currently doctors form a
monopoly and restrict health care to keep their incomes high, you might
think efficiency would increase by providing more health care. But more
likely, if the government mandated increased spending on health care, the
economy would be less efficient because it would give people more health
care than they would choose to pay for. From the point of view of equity, if
poor people are less likely to have adequate health care, providing more
health care would represent an improvement. Each person would have a
more even slice of the economic pie, though the pie would consist of more
health care and less of other goods.
b. When workers are laid off, equity considerations argue for the
unemployment benefits system to provide them with some income until they
can find new jobs. After all, no one plans to be laid off, so unemployment
benefits are a form of insurance. But there’s an efficiency problem why
work if you can get income for doing nothing? The ec onomy isn’t operating
efficiently if people remain unemployed for a long time, and unemployment
benefits encourage unemployment. Thus, there’s a tradeoff between
equity and efficiency. The more generous are unemployment benefits, the
less income is lost by an unemployed person, but the more that person is
encouraged to remain unemployed. So greater equity reduces efficiency.
13. Since average income in the United States has roughly doubled every 35 years, we
are likely to have a better standard of living than our parents, and a much better
standard of living than our grandparents. This is mainly the result of increased
productivity, so that an hour of work produces more goods and services than it used to. Thus incomes have continuously risen over time, as has the standard of living.
14. If Americans save more and it leads to more spending on factories, there will be an
increase in production and productivity, since the same number of workers will have
more equipment to work with. The benefits from higher productivity will go to both the workers, who will get paid more since they're producing more, and the factory
owners, who will get a return on their investments. There is no such thing as a free
lunch, however, because when people save more, they are giving up spending.
They get higher incomes at the cost of buying fewer goods.
15. a. If people have more money, they are probably going to spend more on
goods and services.
b. If prices are sticky, and people spend more on goods and services, then
output may increase, as producers increase output to meet the higher
demand rather than raising prices.
c. If prices can adjust, then the higher spending of consumers will be matched
with increased prices and output won't rise.
16. To make an intelligent decision about whether to reduce inflation, a policymaker
would need to know what causes inflation and unemployment, as well as what
determines the tradeoff between them. Any attempt to reduce inflation will likely
lead to higher unemployment in the short run. A policymaker thus faces a tradeoff
between the benefits of lower inflation compared to the cost of higher
unemployment.
UNIT2
SOLUTIONS TO TEXT PROBLEMS:
Quick Quizzes
1. Economics is like a science because economists devise theories, collect data, and
analyze the data in an attempt to verify or refute their theories. In other words,
economics is based on the scientific method.
Figure 1 shows the production possibilities frontier for a society that produces food
and clothing. Point A is an efficient point (on the frontier), point B is an inefficient
point (inside the frontier), and point C is an infeasible point (outside the frontier).
Figure 1
The effects of a drought are shown in Figure 2. The drought reduces the amount of
food that can be produced, shifting the production possibilities frontier inward.
Figure 2
Microeconomics is the study of how households and firms make decisions and how
they interact in markets. Macroeconomics is the study of economy-wide phenomena, including inflation, unemployment, and economic growth.
2. An example of a positive statement is ―higher taxes discourage work effort‖ (many
other answers are possible). That’s a positive statement because it describes the
effects of higher taxes, describing the world as it is. An example of a normative
statement is ―the government should reduce tax rates.‖ That is a normative
statement because it’s a claim about how the world should be.
Parts of the government that regularly rely on advice from economists are the
Treasury Department in designing tax policy, the Department of Labor in analyzing
data on the employment situation, the Justice Department in enforcing the nation’s
antitrust laws, the Congressional Budget Office in evaluating policy proposals, and the
Federal Reserve in analyzing economic developments (many other answers are
possible).
3. Economic advisers to the president might disagree about a question of policy because
of differing scientific judgments or differences in values.
Questions for Review
1. Economics is like a science because economists use the scientific method. They
devise theories, collect data, and then analyze these data in an attempt to verify or
refute their theories about how the world works. Economists use theory and
observation like other scientists, but they are limited in their ability to run controlled
experiments. Instead, they must rely on natural experiments. 2. Economists make assumptions to simplify problems without substantially affecting the
answer. Assumptions can make the world easier to understand.
3. An economic model cannot describe reality exactly because it would be too
complicated to understand. A model is a simplification that allows the economist to see what is truly important.
4. Figure 3 shows a production possibilities frontier between milk and cookies (PPF1). If
a disease kills half of the economy's cow population, less milk production is possible,
so the PPF shifts inward (PPF2). Note that if the economy produces all cookies, so it doesn't need any cows, then production is unaffected. But if the economy produces any milk at all, then there will be less production possible after the disease hits.
Figure 3
5. The idea of efficiency is that an outcome is efficient if the economy is getting all it can
from the scarce resources it has available. In terms of the production possibilities
frontier, an efficient point is a point on the frontier, such as point A in Figure 4. A
point inside the frontier, such as point B, is inefficient since more of one good could be produced without reducing the production of another good.
Figure 4
6. The two subfields in economics are microeconomics and macroeconomics.
Microeconomics is the study of how households and firms make decisions and how
phenomena.
7. Positive statements are descriptive and make a claim about how the world is, while
normative statements are prescriptive and make a claim about how the world ought
to be. Here is an example. Positive: A rapid growth rate of money is the cause of
inflation. Normative: The government should keep the growth rate of money low.
8. The Council of Economic Advisers is a group of economists who consult with the
president of the United States about economic matters. The Council consists of
three members and a staff of several dozen economists. It writes the annual
Economic Report of the President.
9. Economists sometimes offer conflicting advice to policymakers for two reasons:
(1) economists may disagree about the validity of alternative positive theories about
how the world works; and (2) economists may have different values and, therefore,
different normative views about what public policy should try to accomplish. Problems and Applications
1. Many answers are possible.
2. a. Steel is a fairly uniform commodity, though some firms produce steel of
inferior quality.
b. Novels are each unique, so they are quite distinguishable.
c. Wheat produced by one farmer is completely indistinguishable from wheat
produced by another.
d. Fast food is more distinguishable than steel or wheat, but certainly not as
much as novels.
3. See Figure 5; the four transactions are shown.
Figure 5
4. a. Figure 6 shows a production possibilities frontier between guns and butter.
It is bowed out because when most of the economy’s resources are being
used to produce butter, the frontier is steep and when most of the
economy’s resources are being used to produce gu ns, the frontier is very flat.
When the economy is producing a lot of guns, workers and machines best
suited to making butter are being used to make guns, so each unit of guns
given up yields a large increase in the production of butter. Thus, the
production possibilities frontier is flat. When the economy is producing a lot
of butter, workers and machines best suited to making guns are being used
to make butter, so each unit of guns given up yields a small increase in the
production of butter. Thus, the production possibilities frontier is steep.
b. Point A is impossible for the economy to achieve; it is outside the production
possibilities frontier. Point B is feasible but inefficient because it’s inside the
production possibilities frontier.
Figure 6
c. The Hawks might choose a point like H, with many guns and not much butter.
The Doves might choose a point like D, with a lot of butter and few guns.
d. If both Hawks and Doves reduced their desired quantity of guns by the same
amount, the Hawks would get a bigger peace dividend because the
production possibilities frontier is much steeper at point H than at point D.
As a result, the reduction of a given number of guns, starting at point H,
leads to a much larger increase in the quantity of butter produced than when
starting at point D.
5. See Figure 7. The shape and position of the frontier depend on how costly it is to
maintain a clean environment the productivity of the environmental industry.
Gains in environmental productivity, such as the development of a no-emission auto
engine, lead to shifts of the production-possibilities frontier, like the shift from PPF1 to PPF2 shown in the figure.
Figure 7
6. a. A family's decision about how much income to save is microeconomics.
b. The effect of government regulations on auto emissions is microeconomics.
c. The impact of higher saving on economic growth is macroeconomics.
d. A firm's decision about how many workers to hire is microeconomics.
e. The relationship between the inflation rate and changes in the quantity of
money is macroeconomics.
7. a. The statement that society faces a short-run tradeoff between inflation and
unemployment is a positive statement. It deals with how the economy is,
not how it should be. Since economists have examined data and found that
there is a short-run negative relationship between inflation and
unemployment, the statement is a fact, thus it is a positive statement.
b. The statement that a reduction in the rate of growth of money will reduce
the rate of inflation is a positive statement. Economists have found that
money growth and inflation are very closely related. The statement thus
tells how the world is, and so it is a positive statement.
c. The statement that the Federal Reserve should reduce the rate of growth of
money is a normative statement. It states an opinion about something that
should be done, not how the world is.
d. The statement that society ought to require welfare recipients to look for
jobs is a normative statement. It doesn't state a fact about how the world
is. Instead, it is a statement of how the world should be and is thus a
normative statement.
e. The statement that lower tax rates encourage more work and more saving is
a positive statement. Economists have studied the relationship between
tax rates and work, as well as the relationship between tax rates and saving.
They have found a negative relationship in both cases. So the statement
reflects how the world is, and is thus a positive statement. 8. Two of the statements in Table 2 are clearly normative. They are: "5. If the
federal budget is to be balanced, it should be done over the business cycle rather than yearly" and "9. The government should restructure the welfare system along the
lines of a 'negative income tax.'" Both are suggestions of changes that should be
made, rather than statements of fact, so they are clearly normative statements.
The other statements in the table are positive. All the statements concern how the
world is, not how the world should be. Note that in all cases, even though they are statements of fact, fewer than 100 percent of economists agree with them. You
could say that positive statements are statements of fact about how the world is, but not everyone agrees about what the facts are.
9. As the president, you'd be interested in both the positive and normative views of
economists, but you'd probably be most interested in their positive views.
Economists are on your staff to provide their expertise about how the economy works.
They know many facts about the economy and the interaction of different sectors.
So you would be most likely to call on them about questions of fact positive analysis.
Since you are the president, you are the one who has to make the normative
statements as to what should be done, with an eye to the political consequences.
The normative statements made by economists represent their own views, not
necessarily your views or the electorate’s views.
10. There are many possible answers.
11. As of this writing, the chairman of the Federal Reserve is Alan Greenspan, the chair of
the Council of Economic Advisers is R. Glen Hubbard, and the secretary of the
treasury is Paul H. O’Neill.
12. As time goes on, you might expect economists to disagree less about public policy
because they will have opportunities to observe different policies that are put into
place. As new policies are tried, their results will become known, and they can be
evaluated better. It's likely that the disagreement about them will be reduced after they've been tried in practice. For example, many economists thought that wage
and price controls would be a good idea for keeping inflation under control, while
others thought it was a bad idea. But when the controls were tried in the early
1970s, the results were disastrous. The controls interfered with the invisible hand of the marketplace and shortages developed in many markets. As a result, most
economists are now convinced that wage and price controls are a bad idea for
controlling inflation.
But it is unlikely that the differences between economists will ever be completely
eliminated. Economists differ on too many aspects of how the world works. Plus,
even as some policies get tried out and are either accepted or rejected, creative
economists keep coming up with new ideas.
UNIT4
SOLUTIONS TO TEXT PROBLEMS:
Quick Quizzes
1. A market is a group of buyers (who determine demand) and a group of sellers (who
determine supply) of a particular good or service. A competitive market is one in
which there are many buyers and many sellers of an identical product so that each
has a negligible impact on the market price.
2. Here’s an example of a demand schedule for pizza:
Price of Pizza Slice Number of Pizza Slices Demanded $ 0.00 10
0.25 9
0.50 8
0.75 7
1.00 6
1.25 5
1.50 4
1.75 3
2.00 2
2.25 1
2.50 0
The demand curve is graphed in Figure 1.
Figure 1
Examples of things that would shift the demand curve include changes in income,
prices of related goods like soda or hot dogs, tastes, expectations about future
income or prices, and the number of buyers.
A change in the price of pizza would not shift this demand curve; it would only lead us
to move from one point to another along the same demand curve.
3. Here is an example of a supply schedule for pizza:
Price of Pizza Slice Number of Pizza Slices Supplied
$ 0.00 0
0.25 100
0.50 200
0.75 300
1.00 400
1.25 500
1.50 600
1.75 700
2.00 800
2.25 900
2.50 1000
The supply curve is graphed in Figure 2.
Figure 2
Examples of things that would shift the supply curve include changes in prices of
inputs like tomato sauce and cheese, changes in technology like more efficient pizza
ovens or automatic dough makers, changes in expectations about the future price of
pizza, or a change in the number of sellers.
A change in the price of pizza would not shift this supply curve; it would only move
from one point to another along the same supply curve.
4. If the price of tomatoes rises, the supply curve for pizza shifts to the left because of
the increased price of an input into pizza production, but there is no effect on demand.
The shift to the left of the supply curve causes the equilibrium price to rise and the
equilibrium quantity to decline, as Figure 3 shows.
If the price of hamburgers falls, the demand curve for pizza shifts to the left because
the lower price of hamburgers will lead consumers to buy more hamburgers and less pizza, but there is no effect on supply. The shift to the left of the demand curve
causes the equilibrium price to fall and the equilibrium quantity to decline, as Figure 4 shows.
Figure 3
Figure 4
Questions for Review
1. A competitive market is a market in which there are many buyers and many sellers of
an identical product so that each has a negligible impact on the market price. Other types of markets include monopoly, in which there is only one seller, oligopoly, in
which there are a few sellers that do not always compete aggressively, and
monopolistically competitive markets, in which there are many sellers, each offering a
slightly different product.
2. The quantity of a good that buyers demand is determined by the price of the good,
income, the prices of related goods, tastes, expectations, and the number of buyers.
3. The demand schedule is a table that shows the relationship between the price of a
good and the quantity demanded. The demand curve is the downward-sloping line
relating price and quantity demanded. The demand schedule and demand curve are related because the demand curve is simply a graph showing the points in the
demand schedule.
The demand curve slopes downward because of the law of demand—other things
equal, when the price of a good rises, the quantity demanded of the good falls.
People buy less of a good when its price rises, both because they cannot afford to buy as much and because they switch to purchasing other goods.
4. A change in consumers' tastes leads to a shift of the demand curve. A change in
price leads to a movement along the demand curve.
5. Since Popeye buys more spinach when his income falls, spinach is an inferior good for
him. Since he buys more spinach, but the price of spinach is unchanged, his demand curve for spinach shifts out as a result of the decrease in his income.
6. The quantity of a good that sellers supply is determined by the price of the good,
input prices, technology, expectations, and the number of sellers.
7. A supply schedule is a table showing the relationship between the price of a good and
the quantity a producer is willing and able to supply. The supply curve is the
upward-sloping line relating price and quantity supplied. The supply schedule and
the supply curve are related because the supply curve is simply a graph showing the points in the supply schedule.
The supply curve slopes upward because when the price is high, suppliers' profits
increase, so they supply more output to the market. The result is the law of
supply—other things equal, when the price of a good rises, the quantity supplied of
the good also rises.
8. A change in producers' technology leads to a shift in the supply curve. A change in
price leads to a movement along the supply curve.
9. The equilibrium of a market is the point at which the quantity demanded is equal to
quantity supplied. If the price is above the equilibrium price, sellers want to sell
more than buyers want to buy, so there is a surplus. Sellers try to increase their
sales by cutting prices. That continues until they reach the equilibrium price. If the price is below the equilibrium price, buyers want to buy more than sellers want to sell, so there is a shortage. Sellers can raise their price without losing customers. That continues until they reach the equilibrium price.
10. When the price of beer rises, the demand for pizza declines, because beer and pizza
are complements and people want to buy less beer. When we say the demand for
pizza declines, we mean that the demand curve for pizza shifts to the left as in Figure
5. The supply curve for pizza is not affected. With a shift to the left in the demand curve, the equilibrium price and quantity both decline, as the figure shows. Thus the quantity of pizza supplied and demanded both fall. In sum, supply is unchanged, demand is decreased, quantity supplied declines, quantity demanded declines, and the price falls.
Figure 5
11. Prices play a vital role in market economies because they bring markets into
equilibrium. If the price is different from its equilibrium level, quantity supplied and
quantity demanded are not equal. The resulting surplus or shortage leads suppliers to adjust the price until equilibrium is restored. Prices thus serve as signals that
guide economic decisions and allocate scarce resources.
Problems and Applications
1. a. Cold weather damages the orange crop, reducing the supply of oranges.
This can be seen in Figure 6 as a shift to the left in the supply curve for
oranges. The new equilibrium price is higher than the old equilibrium price.
Figure 6
b. People often travel to the Caribbean from New England to escape cold
weather, so demand for Caribbean hotel rooms is high in the winter. In the
summer, fewer people travel to the Caribbean, since northern climes are
more pleasant. The result, as shown in Figure 7, is a shift to the left in the
demand curve. The equilibrium price of Caribbean hotel rooms is thus
lower in the summer than in the winter, as the figure shows.
Figure 7
c. When a war breaks out in the Middle East, many markets are affecte
d.
Since much oil production takes place there, the war disrupts oil supplies,
shifting the supply curve for gasoline to the left, as shown in Figure 8. The
result is a rise in the equilibrium price of gasoline. With a higher price for
gasoline, the cost of operating a gas-guzzling automobile, like a Cadillac, will
increase. As a result, the demand for used Cadillacs will decline, as people
in the market for cars will not find Cadillacs as attractive. In addition, some
people who already own Cadillacs will try to sell them. The result is that the
demand curve for used Cadillacs shifts to the left, while the supply curve
shifts to the right, as shown in Figure 9. The result is a decline in the
equilibrium price of used Cadillacs.
Figure 8 Figure 9
2. The statement that "an increase in the demand for notebooks raises the quantity of
notebooks demanded, but not the quantity supplied," in general, is false. As Figure
10 shows, the increase in demand for notebooks results in an increased quantity
supplied. The only way the statement would be true is if the supply curve was a
vertical line, as shown in Figure 11.
Figure 10
Figure 11
3. a. If people decide to have more children (a change in tastes), they will want
larger vehicles for hauling their kids around, so the demand for minivans will
increase. Supply won't be affected. The result is a rise in both price and
quantity, as Figure 12 shows.
Figure 12
b. If a strike by steelworkers raises steel prices, the cost of producing a minivan
rises (a rise in input prices), so the supply of minivans decreases. Demand
won't be affected. The result is a rise in the price of minivans and a decline
in the quantity, as Figure 13 shows.
Figure 13c. The development of new automated machinery for the production of
minivans is an improvement in technology. The reduction in firms' costs
results in an increase in supply. Demand isn't affected. The result is a
decline in the price of minivans and an increase in the quantity, as Figure 14
shows.
Figure 14
d. The rise in the price of sport utility vehicles affects minivan demand because
sport utility vehicles are substitutes for minivans (that is, there is a rise in the
price of a related good). The result is an increase in demand for minivans.
Supply is not affected. In equilibrium, the price and quantity of minivans
both rise, as Figure 12 shows.
e. The reduction in peoples' wealth caused by a stock-market crash reduces
their income, leading to a reduction in the demand for minivans, since
minivans are likely a normal good. S upply isn’t affected. As a result, both
price and quantity decline, as Figure 15 shows.
Figure 15
4. Technological advances that reduce the cost of producing computer chips represent a
decline in an input price for producing a computer. The result is a shift to the right in the supply of computers, as shown in Figure 16. The equilibrium price falls and the equilibrium quantity rises, as the figure shows.
Figure 16
Since computer software is a complement to computers, the lower equilibrium price of computers increases the demand for software. As Figure 17 shows, the result is a
rise in both the equilibrium price and quantity of software.
Figure 17
Since typewriters are substitutes for computers, the lower equilibrium price of
computers reduces the demand for typewriters. As Figure 18 shows, the result is a
decline in both the equilibrium price and quantity of typewriters.
Figure 18
5. a. When a hurricane in South Carolina damages the cotton crop, it raises input
prices for producing sweatshirts. As a result, the supply of sweatshirts
shifts to the left, as shown in Figure 19. The new equilibrium has a higher
price and lower quantity of sweatshirts.
Figure 19
b. A decline in the price of leather jackets leads more people to buy leather
jackets, reducing the demand for sweatshirts. The result, shown in Figure
20, is a decline in both the equilibrium price and quantity of sweatshirts.
Figure 20
c. The effects of colleges requiring students to engage in morning calisthenics
in appropriate attire raises the demand for sweatshirts, as shown in Figure
21. The result is an increase in both the equilibrium price and quantity of
sweatshirts.
Figure 21
d. The invention of new knitting machines increases the supply of sweatshirts.
As Figure 22 shows, the result is a reduction in the equilibrium price and an
increase in the equilibrium quantity of sweatshirts.
Figure 22
6. A temporarily high birth rate in the year 2005 leads to opposite effects on the price of
babysitting services in the years 2010 and 2020. In the year 2010, there are more
5-year olds who need sitters, so the demand for babysitting services rises, as shown in Figure 23. The result is a higher price for babysitting services in 2010. However, in the year 2020, the increased number of 15-year olds shifts the supply of babysitting services to the right, as shown in Figure 24. The result is a decline in the price of
babysitting services.
Figure 23 Figure 24
7. Since ketchup is a complement for hot dogs, when the price of hot dogs rises, the
quantity demanded of hot dogs falls, thus reducing the demand for ketchup, causing
both price and quantity of ketchup to fall. Since the quantity of ketchup falls, the
demand for tomatoes by ketchup producers falls, so both price and quantity of
tomatoes fall. When the price of tomatoes falls, producers of tomato juice face
lower input prices, so the supply curve for tomato juice shifts out, causing the price of
tomato juice to fall and the quantity of tomato juice to rise. The fall in the price of
tomato juice causes people to substitute tomato juice for orange juice, so the demand
for orange juice declines, causing the price and quantity of orange juice to fall. Now
you can see clearly why a rise in the price of hot dogs leads to a fall in price of orange
juice!
Figure 25
8. a. Cigars and chewing tobacco are substitutes for cigarettes, since a higher
price for cigarettes would increase the demand for cigars and chewing
tobacco.
b. An increase in the tax on cigarettes leads to increased demand for cigars and
chewing tobacco. The result, as shown in Figure 25 for cigars, is a rise in
both the equilibrium price and quantity of cigars and chewing tobacco.
c. The results in part (b) showed that a tax on cigarettes leads people to
substitute cigars and chewing tobacco for cigarettes when the tax on
cigarettes rises. To reduce total tobacco usage, policymakers might also
want to increase the tax on cigars and chewing tobacco, or pursue some
type of public education program.
9. Quantity supplied equals quantity demanded at a price of $6 and quantity of 81 pizzas
(Figure 26). If price were greater than $6, quantity supplied would exceed quantity
demanded, so suppliers would reduce their price to gain sales. If price were less
than $6, quantity demanded would exceed quantity supplied, so suppliers could raise
their price without losing sales. In both cases, the price would continue to adjust
until it reached $6, the only price at which there is neither a surplus nor a shortage.
Figure 26
10. a. If the price of flour falls, since flour is an ingredient in bagels, the supply
curve for bagels would shift to the right. The result, shown in Figure 27,
would be a fall in the price of bagels and a rise in the equilibrium quantity of
bagels.
Figure 27
Since cream cheese is a complement to bagels, the fall in the equilibrium price of bagels increases the demand for cream cheese, as shown in Figure 28. The result is a rise in both the equilibrium price and quantity of cream cheese. So, a fall in the price of flour indeed raises both the equilibrium price of cream cheese and the equilibrium quantity of bagels.
Figure 28
What happens if the price of milk falls? Since milk is an ingredient in cream cheese, the fall in the price of milk leads to an increase in the supply of cream cheese. This leads to a decrease in the price of cream cheese (Figure 29), rather than a rise in the price of cream cheese. So a fall in the price of milk could not have been responsible for the pattern observed.
Figure 29
b. In part (a), we found that a fall in the price of flour led to a rise in the price
of cream cheese and a rise in the equilibrium quantity of bagels. If the
price of flour rose, the opposite would be true; it would lead to a fall in the
price of cream cheese and a fall in the equilibrium quantity of bagels. Since
the question says the equilibrium price of cream cheese has risen, it could
not have been caused by a rise in the price of flour.
What happens if the price of milk rises? From part (a), we found that a fall
in the price of milk caused a decline in the price of cream cheese, so a rise in
the price of milk would cause a rise in the price of cream cheese. Since
bagels and cream cheese are complements, the rise in the price of cream
cheese would reduce the demand for bagels, as Figure 30 shows. The
result is a decline in the equilibrium quantity of bagels. So a rise in the price
of milk does cause both a rise in the price of cream cheese and a decline in
the equilibrium quantity of bagels.
Figure 30
11. a. As Figure 31 shows, the supply curve is vertical. The constant quantity
supplied makes sense because the basketball arena has a fixed number of
seats no matter what the price.
Figure 31
b. Quantity supplied equals quantity demanded at a price of $8. The
equilibrium quantity is 8,000 tickets.
c.
Price Quantity Demanded Quantity Supplied
$ 4 14,000 8,000
8 11,000 8,000
12 8,000 8,000
16 5,000 8,000
20 2,000 8,000
The new equilibrium price will be $12, which equates quantity demanded to
quantity supplied. The equilibrium quantity is 8,000 tickets.
12. The executives are confusing changes in demand with changes in quantity demanded.
Figure 32 shows the demand curve prior to the marketing campaign (D1), and after
the campaign (D2). The marketing campaign increased the demand for champagne, as shown, leading to a higher equilibrium price and quantity. The influence of the
higher price on demand is already reflected in the outcome. It is impossible for the scenario outlined by the executives to occur.
Figure 32
13. Equilibrium occurs where quantity demanded is equal to quantity supplied. Thus:
Q d = Q s
1,600 – 300P = 1,400 + 700P
200 = 1,000P
P = $0.20
Q d = 1,600 – 300(0.20) = 1,600 – 60 = 1,540
Q s = 1,400 + 700(0.20) = 1,400 + 140 = 1,540.
The equilibrium price of a chocolate bar is $0.20 and the equilibrium quantity is 1,540 bars.
14. A perfectly competitive market is a market where there are many buyers and sellers of
an identical product. No buyer or seller has the ability to influence the price of the
product.
No, ice cream is probably not a very good example of a perfectly competitive market.
Each competitor sells a product that may taste differently or may come in a different variety of flavors. The market for ice cream is better characterized as a
monopolistically competitive market.
UNIT5
SOLUTIONS TO TEXT PROBLEMS:
Quick Quizzes
1. The price elasticity of demand is a measure of how much the quantity demanded of a
good responds to a change in the price of that good, computed as the percentage
change in quantity demanded divided by the percentage change in price.
The relationship between total revenue and the price elasticity of demand is: (1)
when demand is inelastic (a price elasticity less than 1), a price increase raises total
revenue, and a price decrease reduces total revenue; (2) when demand is elastic (a
price elasticity greater than 1), a price increase reduces total revenue, and a price
decrease raises total revenue; and (3) when demand is unit elastic (a price elasticity
equal to 1), a change in price does not affect total revenue.
2. The price elasticity of supply is a measure of how much the quantity supplied of a
good responds to a change in the price of that good, computed as the percentage
change in quantity supplied divided by the percentage change in price.
The price elasticity of supply might be different in the long run than in the short run
because over short periods of time, firms cannot easily change the size of their
factories to make more or less of a good. Thus, in the short run, the quantity
supplied is not very responsive to the price. However, over longer periods, firms can build new factories, expand existing factories, or close old ones, or they can enter or exit a market. So, in the long run, the quantity supplied can respond substantially to the price.
3. A drought that destroys half of all farm crops could be good for farmers (at least those
unaffected by the drought) if the demand for the crops is inelastic. The shift to the left of the supply curve leads to a price increase that raises total revenue because the price elasticity is less than one.
Even though a drought could be good for farmers, they would not destroy their crops in the absence of a drought because no one farmer would have an incentive to
destroy his crops, since he takes the market price as given. Only if all farmers
destroyed their crops together, for example through a government program, would
this plan work to make farmers better off.
Questions for Review
1. The price elasticity of demand measures how much the quantity demanded responds
to a change in price. The income elasticity of demand measures how much the
quantity demanded responds to changes in consumer income.
2. The determinants of the price elasticity of demand include how available close
substitutes are, whether the good is a necessity or a luxury, how broadly defined the market is, and the time horizon. Luxury goods have greater price elasticities than
necessities, goods with close substitutes have greater elasticities, goods in more
narrowly defined markets have greater elasticities, and the elasticity of demand is
higher the longer the time horizon.
3. An elasticity greater than one means that demand is elastic. When the elasticity is
greater than one, the percentage change in quantity demanded exceeds the
percentage change in price. When the elasticity equals zero, demand is perfectly
inelastic. There is no change in quantity demanded when there is a change in price.
4. Figure 1 presents a supply-and-demand diagram, showing equilibrium price,
equilibrium quantity, and the total revenue received by producers. Total revenue
equals the equilibrium price times the equilibrium quantity, which is the area of the
rectangle shown in the figure.
Figure 1
5. If demand is elastic, an increase in price reduces total revenue. With elastic demand,
the quantity demanded falls by a greater percentage than the percentage increase in price. As a result, total revenue declines.
6. A good with an income elasticity less than zero is called an inferior good because as
income rises, the quantity demanded declines.
7. The price elasticity of supply is calculated as the percentage change in quantity
supplied divided by the percentage change in price. It measures how much the
quantity supplied responds to changes in the price.
8. The price elasticity of supply of Picasso paintings is zero, since no matter how high
price rises, no more can ever be produced.
9. The price elasticity of supply is usually larger in the long run than it is in the short run.
Over short periods of time, firms cannot easily change the size of their factories to
make more or less of a good, so the quantity supplied is not very responsive to price.
Over longer periods, firms can build new factories or close old ones, so the quantity
supplied is more responsive to price.
10. OPEC was unable to maintain a high price through the 1980s because the elasticity of
supply and demand was more elastic in the long run. When the price of oil rose,
producers of oil outside of OPEC increased oil exploration and built new extraction
capacity. Consumers responded with greater conservation efforts. As a result,
supply increased and demand fell, leading to a lower price for oil in the long run. Problems and Applications
1. a. Mystery novels have more elastic demand than required textbooks, because
mystery novels have close substitutes and are a luxury good, while required
textbooks are a necessity with no close substitutes. If the price of mystery
novels were to rise, readers could substitute other types of novels, or buy
fewer novels altogether. But if the price of required textbooks were to rise,
students would have little choice but to pay the higher price. Thus the
quantity demanded of required textbooks is less responsive to price than the
quantity demanded of mystery novels.
b. Beethoven recordings have more elastic demand than classical music
recordings in general. Beethoven recordings are a narrower market than
classical music recordings, so it's easy to find close substitutes for them. If
the price of Beethoven recordings were to rise, people could substitute other
classical recordings, like Mozart. But if the price of all classical recordings
were to rise, substitution would be more difficult (a transition from classical
music to rap is unlikely!). Thus the quantity demanded of classical
recordings is less responsive to price than the quantity demanded of
Beethoven recordings.
c. Heating oil during the next five years has more elastic demand than heating
oil during the next six months. Goods have a more elastic demand over
longer time horizons. If the price of heating oil were to rise temporarily,
consumers couldn't switch to other sources of fuel without great expense.
But if the price of heating oil were to be high for a long time, people would
gradually switch to gas or electric heat. As a result, the quantity demanded
of heating oil during the next six months is less responsive to price than the
quantity demanded of heating oil during the next five years.
d. Root beer has more elastic demand than water. Root beer is a luxury with
close substitutes, while water is a necessity with no close substitutes. If the
price of water were to rise, consumers have little choice but to pay the
higher price. But if the price of root beer were to rise, consumers could
easily switch to other sodas. So the quantity demanded of root beer is
more responsive to price than the quantity demanded of water.
2. a. For business travelers, the price elasticity of demand when the price of
tickets rises from $200 to $250 is [(2,000 - 1,900)/1,950]/[(250 - 200)/225]
= 0.05/0.22 = 0.23. For vacationers, the price elasticity of demand when
the price of tickets rises from $200 to $250 is [(800 - 600)/700] / [(250 -
200)/225] = 0.29/0.22 = 1.32.
b. The price elasticity of demand for vacationers is higher than the elasticity for
business travelers because vacationers can choose more easily a different
mode of transportation (like driving or taking the train). Business travelers
are less likely to do so since time is more important to them and their
schedules are less adaptable.
3. a. If your income is $10,000, your price elasticity of demand as the price of
compact discs rises from $8 to $10 is [(40 - 32)/36]/[(10 - 8)/9] =0.22/0.22
= 1. If your income is $12,000, the elasticity is [(50 - 45)/47.5]/[(10 -
8)/9] = 0.11/0.22 = 0.5.
b. If the price is $12, your income elasticity of demand as your income
increases from $10,000 to $12,000 is [(30 - 24)/27] / [(12,000 -
10,000)/11,000] = 0.22/0.18 = 1.22. If the price is $16, your income
elasticity of demand as your income increases from $10,000 to $12,000 is
[(12 - 8)/10] / [(12,000 - 10,000)/11,000] = 0.40/0.18 = 2.2.
4. a. If Emily always spends one-third of her income on clothing, then her income
elasticity of demand is one, since maintaining her clothing expenditures as a
constant fraction of her income means the percentage change in her
quantity of clothing must equal her percentage change in income. For
example, suppose the price of clothing is $30, her income is $9,000, and she
purchases 100 clothing items. If her income rose 10 percent to $9,900,
she'd spend a total of $3,300 on clothing, which is 110 clothing items, a 10
percent increase.
b. Emily's price elasticity of clothing demand is also one, since every
percentage point increase in the price of clothing would lead her to reduce
her quantity purchased by the same percentage. Again, suppose the price
of clothing is $30, her income is $9,000, and she purchases 100 clothing
items. If the price of clothing rose 1 percent to $30.30, she would purchase
99 clothing items, a 1 percent reduction. [Note: This part of the problem
can be confusing to students if they have an example with a larger
percentage change and they use the point elasticity. Only for a small
percentage change will the answer work with an elasticity of one.
Alternatively, they can get the second part if they use the midpoint method
for any size change.]
c. Since Emily spends a smaller proportion of her income on clothing, then for
any given price, her quantity demanded will be lower. Thus her demand
curve has shifted to the left. But because she'll again spend a constant
fraction of her income on clothing, her income and price elasticities of
demand remain one.
5. a. With a 4.3 percent decline in quantity following a 20 percent increase in price,
the price elasticity of demand is only 4.3/20 = 0.215, which is fairly inelastic.
b. With inelastic demand, the Transit Authority's revenue rises when the fare
rises.
c. The elasticity estimate might be unreliable because it is only the first month
after the fare increase. As time goes by, people may switch to other means
of transportation in response to the price increase. So the elasticity may be
larger in the long run than it is in the short run.
6. Tom's price elasticity of demand is zero, since he wants the same quantity regardless
of the price. Jerry's price elasticity of demand is one, since he spends the same
amount on gas, no matter what the price, which means his percentage change in
quantity is equal to the percentage change in price.
7. To explain the fact that spending on restaurant meals declines more during economic
downturns than does spending on food to be eaten at home, economists look at the
income elasticity of demand. In economic downturns, people have lower income.
To explain the fact, the income elasticity of restaurant meals must be larger than the income elasticity of spending on food to be eaten at home.
8. a. With a price elasticity of demand of 0.4, reducing the quantity demanded of
cigarettes by 20 percent requires a 50 percent increase in price, since 20/50
= 0.4. With the price of cigarettes currently $2, this would require an
increase in the price to $3.33 a pack using the midpoint method (note that
($3.33 - $2)/$2.67 = .50).
b. The policy will have a larger effect five years from now than it does one year
from now. The elasticity is larger in the long run, since it may take some
time for people to reduce their cigarette usage. The habit of smoking is
hard to break in the short run.
c. Since teenagers don't have as much income as adults, they are likely to have
a higher price elasticity of demand. Also, adults are more likely to be
addicted to cigarettes, making it more difficult to reduce their quantity
demanded in response to a higher price.
9. You’d expect the price elasticity of demand to be higher in the market for vanilla ice
cream than for all ice cream because vanilla ice cream is a narrower category and
other flavors of ice cream are close substitutes for vanilla.
You'd expect the price elasticity of supply to be larger for vanilla ice cream than for all ice cream. A producer of vanilla ice cream could easily adjust the quantity of vanilla ice cream and produce other types of ice cream. But a producer of ice cream would have a more difficult time adjusting the overall quantity of ice cream.
10. a. As Figure 2 shows, in both markets, the increase in supply reduces the
equilibrium price and increases the equilibrium quantity.
b. In the market for pharmaceutical drugs, with inelastic demand, the increase
in supply leads to a relatively large decline in the price and not much of an
increase in quantity.
Figure 2
c. In the market for computers, with elastic demand, the increase in supply
leads to a relatively large increase in quantity and not much of a decline in
price.
d. In the market for pharmaceutical drugs, since demand is inelastic, the
percentage increase in quantity will be less than the percentage decrease in
price, so total consumer spending will decline. In contrast, since demand is
elastic in the market for computers, the percentage increase in quantity will
be greater than the percentage decrease in price, so total consumer
spending will increase.
11. a. As Figure 3 shows, in both markets the increase in demand increases both
the equilibrium price and the equilibrium quantity.
b. In the market for beachfront resorts, with inelastic supply, the increase in
demand leads to a relatively large increase in the price and not much of an
increase in quantity.
c. In the market for automobiles, with elastic supply, the increase in demand
leads to a relatively large increase in quantity and not much of an increase in
price.
d. In both markets, total consumer spending rises, since both equilibrium price
and equilibrium quantity rise.
Figure 3
12. a. Farmers whose crops weren't destroyed benefited because the destruction
of some of the crops reduced the supply, causing the equilibrium price to
rise.
b. To tell whether farmers as a group were hurt or helped by the floods, you'd
need to know the price elasticity of demand. It could be that the additional
income earned by farmers whose crops weren't destroyed rose more
because of the higher prices than farmers whose crops were destroyed, if
demand is inelastic.
13. A worldwide drought could increase the total revenue of farmers if the price elasticity
of demand for grain is inelastic. The drought reduces the supply of grain, but if
demand is inelastic, the reduction of supply causes a large increase in price. Total
farm revenue would rise as a result. If there's only a drought in Kansas, Kansas’
production isn't a large enough proportion of the total farm product to have much
impact on the price. As a result, price does not change (or changes by only a slight amount), while the output of Kansas farmers declines, thus reducing their income.
14. When productivity increases for all farmland at a point in time, the increased
productivity leads to a rise in farmland prices, since more output can be produced on
a given amount of land. But prior to the technological improvements, the
productivity of farmland depended mainly on the prevailing weather conditions.
There was little opportunity to substitute land with worse weather conditions for land with better weather conditions. As technology improved over time, it became much easier to substitute one type of land for another. So the price elasticity of supply for farmland increased over time, since now land with bad weather is a better substitute for land with good weather. The increased supply of land reduced farmland prices.
As a result, productivity and farmland prices are negatively related over time.
UNIT6
SOLUTIONS TO TEXT PROBLEMS:
Quick Quizzes
1. A price ceiling is a legal maximum on the price at which a good can be sold.
Examples of price ceilings include rent control, price controls on gasoline in the 1970s, and price ceilings on water during a drought. A price floor is a legal minimum on the price at which a good can be sold. Examples of price floors include the minimum
wage and farm-support prices. A price ceiling leads to a shortage, if the ceiling is
binding, because suppliers won’t produce enough goods to meet demand unless the
price is allowed to rise above the ceiling. A price floor leads to a surplus, if the floor is binding, because suppliers produce more goods than are demanded unless the
price is allowed to fall below the floor.
2. With no tax, as shown in Figure 1, the demand curve is D1 and the supply curve is S.
The equilibrium price is P1 and the equilibrium quantity is Q1. If the tax is imposed on car buyers, the demand curve shifts down by the amount of the tax ($1000) to D2.
The downward shift in the demand curve leads to a decline in the equilibrium price to
P2 (the amount received by sellers from buyers) and a decline in the equilibrium
quantity to Q2. The price received by sellers declines by P1 – P2, shown in the figure as ? P S. Buyers pay a total of P2 + $1,000, an increase in what they pay of P2 +
$1,000 - P1, shown in the figure as ? P B.
Figure 1
If the tax is imposed on car sellers, as shown in Figure 2, the supply curve shifts up by the amount of the tax ($1000) to S2. The upward shift in the supply curve leads to a rise in the equilibrium price to P2 (the amount received by sellers from buyers) and a decline in the equilibrium quantity to Q2. The price paid by buyers declines by P1 - P2, shown in the figure as ?P B. Sellers receive P2 and pay taxes of $1,000, receiving on net P2 - $1,000, a decrease in what they receive by P1 - (P2 - $1,000), shown in the
figure as ?P S.
23章 微观经济学：研究家庭和企业如何做出决策，以及它们如何在市场上相互影响。 宏观经济学：研究整体经济现象，包括通货膨胀，失业和经济增长。 国内生产总值（GDP ）：在某一既定时期一个国家内生产的所有最终物品与劳务的市场价值。 消费：家庭除购买新住房之外用于物品与劳务的支出。 投资：用于资本设备、存货和建筑物的支出，包括家庭用于购买新住房的支出。 政府购买：地方、州和联邦政府用于物品与劳务的支出。 净出口：外国人对国内生产的物品的支出（出口）减国内居民对外国物品的支出（进口）。 名义GDP ：按现期价格评价的物品与劳务的生产。 真实GDP ：按不变价格评价的物品与劳务的生产。 GDP 平减指数：用名义GDP 与真实GDP 的比率乘以100计算的物价水平衡量指标。 100GDP GDP GDP ?=真实名义平减指数 %100GDP GDP -GDP ?=平减指数 第一年的平减指数第一年的平减指数第二年的第二年的通货膨胀率 24章 消费物价指数（CPI ）：普通消费者所购买的物品与劳务的总费用的衡量指标。 100?=基年一篮子的价格 的价格当年一篮子物品与劳务消费物价指数 通货膨胀率：从前一个时期以来物价指数变动的百分比。 %100CPI CPI -CPI ?=第一年第一年第二年第二年的通货膨胀率 生产物价指数：企业购买的一篮子物品与劳务的费用的衡量指标。 年的物价水平 今天的物价水平年美元的数量今天的美元的数量T T ?= 指数化：根据法律或协议按照通货膨胀的影响对美元数量的自动调整。 名义利率：通常公布的、未根据通货膨胀的影响校正的利率。 真实利率：根据通货膨胀的英雄校正过得利率。 25章 生产率：每单位劳动投入所生产的物品与劳务的数量。 物质资本：用于生产物品与劳务的设备和建筑物存量。 人力资本：工人通过教育、培训和经验而获得的知识与技能。 自然资源：由自然界提供的用于生产物品和劳务的投入，如土地、河流和矿藏。 技术知识：社会对生产物品与劳务的最好方法的了解。 收益递减：随着投入量的增加，每一单位额外投入得到的收益减少的特性。 追赶效应：开始时贫穷的国家倾向于比开始时富裕的国家增长更快的特征。 26章 金融体系：经济中促使一个人的储蓄与另一个人的投资相匹配的一组机构。 金融市场：储蓄者可以借以直接向借款者提供资金的金融机构。
产大量物品与劳务，才能使本国居民享有在国际贸易环境下的高生活水平。2．假定社会决定减少消费并增加投资。 A．这种变化会如何影响经济增长? 答：当社会决定减少消费并增加投资时，会使社会的储蓄增加，更多的资源用于生产资本品，结果，资本存量增加，引起生产率提高和 GDP 增长得更为迅速。B．哪些社会群体会从这种变化中获益?哪些集团会受到损害? 答：拥有资本品的人会从这种变化中获益，如拥有较多的物质资本和人力资本的人。而那些依靠政府援助的人将从这种变化中受损，因为社会减少了现期物品与劳务的消费。 3．社会选择把多少资源用于消费和把多少资源用于投资。这些决策中的一部分涉及私人支出；另一些涉及政府支出。 A．说明代表消费的一些私人支出形式，以及代表投资的一些私人支出形式。国民收入账户把学费作为消费支出的一部分。按你的看法，把资源用于教育是一种消费的形式，还是一种投资的形式。 答：如家庭购买食物和服装是消费的私人支出形式，而个人购买新住房、企业对厂房和设备的投资是代表投资的私人支出形式。资源用于教育即可以看作是一种消费的形式，也可以看作是一种投资的形式。 B．说明代表消费的一些政府支出形式，以及代表投资的一些政府支出形式。按你的看法，我们应该把政府用于医疗计划的支出作为一种消费的形式，还是投资的形式？你能区分青年人的医疗计划和老年人的医疗计划吗？ 答：社会保险、国防和退伍军人津贴等是代表消费的一些政府支出形式，政府修筑铁路、核电站是代表投资的一些政府支出形式。政府用于医疗计划的支出是一种对人力资本的投资。与老年人的医疗计划相比，青年人的医疗计划更接近对人力资本的投资。 4．投资于资本的机会成本是什么？你认为一国有可能对资本“过度投资”吗？人力资本投资的机会成本是什么？你认为一国可能对人力资本“过度投资”吗？解释之。 答：投资于资本的机会成本是牺牲现期的物品和劳务的消费。一国有可能对资本“过度投资”。人力资本投资也有机会成本。当学生上学时．他们放弃了他们本可以赚到的收入。即使在人力资本特别稀缺的发展中国家，一国也不会对人力资本“过度投资”，因为一国政府进行人力资本投资的方式是提供更多更好的学校，并鼓励人们利用这些学校。尽管受过教育的工人与未受过教育的工人之间的工资差距很大，但是很多儿童在小小年纪就退学了，因为他们需要用劳动来养家糊口。 5．假设一家完全由德国公民拥有的汽车公司在南卡罗来纳开办了一家新工厂。
微观经济学（曼昆）案例分析练习题 https://www.doczj.com/doc/eb9032451.html,/ 1、假设我们有以下自行车的市场供给与需求表： a．画出自行车的供给曲线和需求曲线。 b．自行车的均衡价格是多少? c．自行车的均衡数量是多少? d．如果自行车的价格是100美元，存在过剩还是短缺?有多少单位过剩或短缺?这将引起价格上升还是下降？ e．如果自行车的价格是400美元，存在过剩还是短缺?有多少单位过剩或短缺?这将引起价格上升还是下降? f.假设自行车市场的工会为增加工资而谈判。此外，再假设这个事件增加了生产成本，使自行车制造不利，而且，在每种自行车价格时减少了自行车供给量20辆。在图4_2中画出新的供给曲线以及原来的供给和需求曲线。自行车市场新的均衡价格和数量是多少? 【参考答案】： a．
b ．300美元。 c ．50辆自行车。 d ．短缺，70—30=40单位，价格将上升。 e ．过剩，60—40=20单位，价格将下降。 f.均衡价格为400美元，均衡数量为40辆自行车。 2、假设《每日新闻》估计，如果它把自己报纸的价格从1美元提高到1．5美元，那么订 户数就将从5万下降到4万。 a ．当用中点法计算弹性时，《每日新闻》的需求价格弹性是多少? b ．使用中点法的好处是什么? c ．如果《每日新闻》只关心总收益最大化，它应该把报纸的价格从1美元提高到1．5美元吗?为什么该提价或不该提价? 【参考答案】： a ．(10000／45000)／(0.50美元/1.25美元)=0.56。 b ．用中点法的好处是，无论你从价格为1美元开始上升到1.5美元，还是从1.5美元开始下降到1美元，弹性的值是相同的。 c ．应该提价。因为需求价格弹性小于1(缺乏弹性)，价格上升将增加总收益。 3、对下列每一对物品，你预期哪一种物品更富有供给弹性?为什么? a ．电视；海滩的地产
Chapter 8 Application: The Costs of Taxation Test A 1. A tax levied on the buyers of a product shifts the a. demand curve upward or to the right. b. demand curve downward or to the left. c. supply curve upward or to the left. d. supply curve downward or to the right. ANSWER: b. demand curve downward or to the left. TYPE: M KEY1: D SECTION: 1 OBJECTIVE: 1 RANDOM: Y 2. When a tax is levied on a good a. buyers are worse off but sellers are not. b. sellers are worse off but buyers are not. c. neither buyers nor sellers are worse off. d. both buyers and sellers are worse off. ANSWER: d. both buyers and sellers are worse off. TYPE: M KEY1: D SECTION: 1 OBJECTIVE: 1 RANDOM: Y 3. When a tax on a good is enacted, a. sellers always bear the full burden of the tax. b. buyers always bear the full burden of the tax. c. buyers and sellers share the burden of the tax regardless of which party it is levied on. d. sellers bear the full burden if the tax is levied on them, but buyers bear the full burden if the tax is levied on them. ANSWER: c. buyers and sellers share the burden of the tax regardless of which party it is levied on. TYPE: M KEY1: C SECTION: 1 OBJECTIVE: 1 RANDOM: Y 4. A tax placed on a good a. causes the price of the good to fall. b. causes the size of the market for the good to shrink. c. affects buyers of the good, but not sellers. d. is usually borne entirely by the seller of the good. ANSWER: b. causes the size of the market for the good to shrink. TYPE: M KEY1: C SECTION: 1 OBJECTIVE: 1 RANDOM: Y 5. When a tax is levied on a good a. the market price falls because demand declines. b. the market price falls because supply falls. c. the market price rises because demand falls. d. a wedge is placed between the price buyers pay and the price sellers receiv e. ANSWER: d. a wedge is placed between the price buyers pay and the price sellers receive. TYPE: M KEY1: C SECTION: 1 OBJECTIVE: 1 RANDOM: Y
第 20 章货币制度 1、为什么银行不持有百分百的准备金？银行持有的准备金量和银行体系所创造的货币量 有什么关系？ 参考答案： 银行不持有百分百的准备金是因为把存款用于放贷并收取利息比持有全部存款更有利 可图。银行持有的准备金量和银行体系通过货币乘数所创造的货币量是相关的。银行的准备金率越低，货币乘数越大，所以银行存款的每一元钱可以创造更多的货币 2、考察以下情况如何影响经济的货币制度。 a、假设雅普岛的居民发现了一种制造石轮的简单方法。这种发现如何影响石轮作为货 币的有用性呢？并解释之。 b、假设美国某个人发现了一种仿造100 美元钞票的简单办法。这种发现将如何影响美 国的货币制度呢？并解释之。 参考答案： a、如果有一种制造石轮的简单方法，雅普岛上的居民就会制造多余的石轮，只要每个 石轮的货币价值大于制造它的成本。结果，人们会自己制造货币，于是就有太多的货币被制 造出来。最有可能的是，人们会停止接受石轮作为货币，而转向其他资产作为交换的媒介 b.如果美国有人发现了伪造百元面值美钞的简单方法，他们就会大量地生产这种假 钞，而降低百元美钞的价值，结果可能是转为使用另一种通货。 3、伯列戈瑞德州银行(BSB)有 2.5 亿美元存款，并保持10％的准备率。 a)列出 BSB的 T 账户。 b) 现在假设BSB的大储户从其账户中提取了1000 万美元现金。如果 BSB决定通过减 少其未清偿贷款量来恢复其准备率，说明它的新T 账户。 c) 解释 BSB的行动对其他银行有什么影响？ d) 为什么 BSB要采取 (b) 中所描述的行为是困难的？讨论BSB恢复其原来准备金率的 另一种方法。 参考答案： a. BSB的 T 账户如下： : 伯列戈瑞德州银行(BSB) 资产负债 准备金$25 million存款$250 million 贷款$225 million b.当 BSB的大储户提取了 1000 万美金现金，而 BSB通过减少其未清偿贷款量来恢复其 准备率，它的 T 账户如下：
问题与应用 1．描写下列每种情况所面临的权衡取舍： A．一个家庭决定是否买一辆新车。 答：如果买新车就要减少家庭其他方面的开支，如：外出旅行，购置新家具；如果不买新车就享受不到驾驶新车外出的方便和舒适。 B．国会议员决定对国家公园支出多少。 答：对国家公园的支出数额大，国家公园的条件可以得到改善，环境会得到更好的保护。但同时，政府可用于交通、邮电等其他公共事业的支出就会减少。 C．一个公司总裁决定是否新开一家工厂。 答：开一家新厂可以扩大企业规模，生产更多的产品。但可能用于企业研发的资金就少了。这样，企业开发新产品、利用新技术的进度可能会减慢。 D．一个教授决定用多少时间备课。 答：教授若将大部分时间用于自己研究，可能会出更多成果，但备课时间减少影响学生授课质量。E．一个刚大学毕业的学生决定是否去读研究生。 答：毕业后参加工作，可即刻获取工资收入；但继续读研究生，能接受更多知识和未来更高收益。2．你正想决定是否去度假。度假的大部分成本((机票、旅馆、放弃的工资))都用美元来衡量，但度假的收益是心理的。你将如何比较收益与成本呢?? 答：这种心理上的收益可以用是否达到既定目标来衡量。对于这个行动前就会作出的既定目标，我们一定有一个为实现目标而愿意承担的成本范围。在这个可以承受的成本范围内，度假如果满足了既定目标，如：放松身心、恢复体力等等，那么，就可以说这次度假的收益至少不小于它的成本。3．你正计划用星期六去从事业余工作，但一个朋友请你去滑雪。去滑雪的真实成本是什么？现在假设你已计划这天在图书馆学习，这种情况下去滑雪的成本是什么？请解释之。 答：去滑雪的真实成本是周六打工所能赚到的工资，我本可以利用这段时间去工作。如果我本计划这天在图书馆学习，那么去滑雪的成本是在这段时间里我可以获得的知识。 4．你在篮球比赛的赌注中赢了100美元。你可以选择现在花掉它或在利率为55%的银行中存一年。现在花掉100美元的机会成本是什么呢? 答：现在花掉100 美元的机会成本是在一年后得到105 美元的银行支付(利息+本金)。 5．你管理的公司在开发一种新产品过程中已经投资500万美元，但开发工作还远远没有完成。在最近的一次会议上，你的销售人员报告说，竞争性产品的进入使你们新产品的预期销售额减少为300万美元。如果完成这项开发还要花费100万美元，你还应该继续进行这项开发吗？为了完成这项开发，你的最高花费应该是多少?? 答：还应该继续这项开发。因为现在它的边际收益是300 万美元，而边际成本是100 万美元。为了完成这项开发我最多能再花300 万美元。只要边际收益大于边际成本，就有利可图。 6．魔力饮料公司的三位经理正在讨论是否要扩大产量。每位经理提出了做出这个决策的一种方法：哈利：我们应该考查一下我们公司的生产率——每个工人生产的加仑数——将上升还是下降。 罗恩：我们应该考查一下我们的平均成本——每个工人的成本——将上升还是下降。 赫敏：我们应该考查一下多卖一加仑饮料的额外收益，大于还是小于额外的成本。你认为谁对？答：我认为赫敏提出的决策方法正确。因为只有多卖一加仑饮料的额外收益大于它的额外成本时，多卖一加仑饮料才是有利可图的。理性人应该考虑边际量。 77．社会保障制度为65岁以上的人提供收入。如果一个社会保障的领取者决定去工作并赚一些钱，他(或她)所领到的社会保障津贴通常会减少。 A．提供社会保障如何影响人们在工作时的储蓄激励? 答：社会保障的提供使人们退休以后仍可以获得收入，以保证生活。因此，人们不用为不能工作时的生活费而发愁，人们在工作时期的储蓄就会减少。
1. Describe some of the trade-offs faced by each of the following: a. a family deciding whether to buy a new car b. a member of Congress deciding how much to spend on national parks c. a company president deciding whether to open a new factory d. a professor deciding how much to prepare for class e. a recent college graduate deciding whether to go to graduate school 2. You are trying to decide whether to take a vacation. Most of the costs of the vacation (airfare, hotel, and forgone wages) are measured in dollars, but the benefits of the vacation are psychological. How can you compare the benefits to the costs? 3. You were planning to spend Saturday working at your part-time job, but a friend asks you to go skiing. What is the true cost of going skiing? Now suppose you had been planning to spend the day studying at the library. What is the cost of going skiing in this case? Explain. 4. You win $100 in a basketball pool. You have a choice between spending the money now or putting it away for a year in a bank account that pays 5 percent interest. What is the opportunity cost of spending the $100 now? 5. The company that you manage has invested $5 million in developing a new product, but the development is not quite finished. At a recent meeting, your salespeople report that the introduction of competing products has reduced the expected sales of your new product to $3 million. If it would cost $1 million to finish development and make the product, should you go ahead and do so? What is the most that you should pay to complete development? 6. The Social Security system provides income for people over age 65. If a recipient of Social Security decides to work and earn some income, the amount he or she receives in Social Security benefits is typically reduced.
曼昆经济学原理答案30—34
第十二篇短期经济波动 第三十一章总需求与总供给 复习题 1．写出当经济进入衰退时下降的两个宏观经济变量的名字。写出当经济进入衰退时上升的一个宏观经济变量的名字。 答：当经济进入衰退时，实际GDP和投资支出下降，失业率上升。 2．画出一个有总需求、短期总供给和长期 总供给的曲线的图。仔细地标出正确的轴。 答： 图31—1 经济的长期均衡 3．列出并解释总需求曲线向右下方倾斜的 三个原因。 答：为了理解总需求曲线向右下 方倾斜的原因，我们必须考察物价水平如何影响消费、投资和净出口的物品与劳务需求量。 (1)庇古的财富效应
物价水平下降使消费者感到更富裕，这又鼓励他们更多地支出，消费支出增加意味着物品与劳务的需求量更大。 (2)凯恩斯的利率效应 较低的物价水平降低了利率，鼓励了家庭和企业更多地支出于投资物品，从而增加了物品与劳务的需求量。 (3)蒙代尔——弗莱明汇率效应 当美国物价水平下降引起美国利率下降时，实际汇率贬值，而且这种贬值刺激了美国的净出口，从而增加了国外对美国物品与劳务的需求量。 由于这三个原因，总需求曲线向右下方倾斜。 4．解释为什么长期总供给曲线是垂线。 答：在长期中，一个经济的物品与劳务的供给取决于它资本与劳动的供给，以及用来把资本与劳动变为物品与劳务的生产技术。由于物价水平并不影响这些实际GDP的长期决定因素，所以长期总供给曲线是一条垂线，即经济的资本、劳动和技术决定了物品与劳务供给量，而且，无论物价水平如何变动，供给量都是相同的。
5．列出并解释为什么短期总供给曲线向右上方倾斜的三种理论。 答：在短期中，总供给曲线向右上方倾斜，也就是说，在一个一两年的时期中，经济中物价总水平的上升增加了物品与劳务的供给量，而物价水平下降倾向于减少物品与劳务供给量。什么因素引起物价水平与产量之间的正相关关系呢?宏观经济学家提出了三种理论说明短期总供给曲线的向右上方倾斜。在每一种理论中，一种特殊的市场不完全性引起经济中供给一方的短期状况与长期不同。虽然每一种理论在细节上不同，但它们具有共同的内容：当物价水平背离了人们预期的物价水平时，供给量就背离了其长期水平或“自然水平”。当物价水平高于预期水平时，产量就高于其自然率。当物价水平低于预期水平时，产量就低于其自然率。 (1)新古典的错觉理论 根据这种理论，物价总水平的变动会暂时误导供给者对他们出售其产品的市场发生的变动的看法。由于这些短期的错觉，供给者对物价水平的变动作出了反应，而这种反应引起了向右上方倾斜的总供给曲线。假设物价总水平降到低于
第一篇导言 第一章经济学十大原理 1．列举三个你在生活中面临的重要权衡取合的例子。 答：①大学毕业后.面临着是否继续深造的选择，选择继续上学攻读研究生学位，就意味着在今后三年中放弃参加工作、赚工资和积累社会经验的机会；2、在学习内容上也面临 着很重要的权衡取舍，如果学习《经济学》，就要减少学习英语或其他专业课的时间，③对 于不多的生活费的分配同样面临权衡取舍，要多买书．就要减少在吃饭、买衣服等其他方面的开支。 2、看一场电影的机会成本是什么? 答：看一场电影的机会成本是在看电影的时间里做其他事情所能获得的最大收益，例如：看书、打零工。 3、水是生活必需的。一杯水的边际利益是大还是小呢? 答：这要看这杯水是在什么样的情况下喝．如果这是一个人五分钟内喝下的第五杯水．那么他的边际利益很小．有可能为负；如果这是一个极度干渴的人喝下的第一杯水，那么他的边际利益将会极大。 4、为什么决策者应该考虑激励? 答：因为人们会对激励做出反应。如果政策改变了激励，它将使人们改变自己的行为，当决策者未能考虑到行为如何由于政策的原因而变化时．他们的政策往往会产生意想不到的效果。 5 为什么各国之间的贸易不像竞赛一样有赢家和输家呢? 答：因为贸易使各国可以专门从事自己最擅长的话动，并从中享有更多的各种各样的物品与劳务。通过贸易使每个国家可供消费的物质财富增加，经济状况变得更好。因此，各 个贸易国之间既是竞争对手，又是经济合作伙伴。在公平的贸易中是“双赢”或者“多赢” 的结果。 6．市场巾的那只“看不见的手”在做什么呢，答：市场中那只“看不见的手”就是商品价格，价格反映商品自身的价值和社会成本， 市场中的企业和家庭在作出买卖决策时都要关注价格。因此．他们也会不自觉地考虑自己行为的（社会）收益和成本。从而，这只“看不见的手”指引着干百万个体决策者在大多数情况下使社会福利趋向最大化。 7 解释市场失灵的两个主要原因，并各举出一个例子。答：市场失灵的主要原因是外部性和市场势力。外部性是一个人的行为对旁观者棉利的影响。当一个人小完全承担（或享受）他的行为所造成的成本（或收益）时，就会产生外部性。举例：如果一个人不承担他在公共场所吸烟的全部成本，他就会毫无顾忌地吸烟。在这种情况下，政府可以通过制定禁止在公共场所吸烟的规章制度来增加经济福利。 市场势力是指一个人（或一小群人）不适当地影响市场价格的能力。例如：某种商品的垄断生产者由于几乎不受市场竞争的影响，可以向消费者收取过高的垄断价格。在这种情况下，规定垄断者收取的价格有可能提高经济效率。 8．为什么生产率是重要的? 答：因为一国的生活水平取决于它生产物品与劳务的能力，而对这种能力的最重要的 衡量度就是生产率。生产率越高，一国生产的物品与劳务量就越多。 9 什么是通货膨胀，什么引起了通货膨胀? 答：通货膨胀是流通中货币量的增加而造成的货币贬值生活中价格总水平上升。货币量增长引起了通货膨胀。 10．短期中通货膨胀与失业如何相关? 答：短期中通货膨胀与失业之间存在着权衡取台，这是由于某些价格调整缓慢造成的。政府为了抑制通货膨胀会减少流通中的货币量，人们可用于支出的货币数量减少了，但是商品价格在短期内是粘性的，仍居高不下．于是社会消费的商品和劳务量减少，消费量减少又引起企业解雇工人。在短期内．对通货膨胀的抑制增加了失业量。 问题与应用
WHAT’S NEW IN THE S EVENTH EDITION: A new Case Study on Left-Digit Bias has been added and a new In the News feature on "Can Brain Science Improve Economics?" has been added. LEARNING OBJECTIVES: By the end of this chapter, students should understand: how to examine problems caused by asymmetric information. the market solutions to asymmetric information. why democratic voting systems may not represent the preferences of society. why people may not always behave as rational maximizers. CONTEXT AND PURPOSE: Chapter 22 is the last chapter in the microeconomics portion of the text. It is the second of two unrelated chapters that introduce students to advanced topics in microeconomics. These two chapters are intended to whet their appetites for further study in economics. The purpose of Chapter 22 is to give students a taste of three topics on the frontier of microeconomic research. The first topic addressed is asymmetric information , a situation when one person in an economic relationship has more relevant knowledge than the other person does. The second topic is political economy , the application of economic tools to the understanding of the functioning of government. The third topic addressed is behavioral economics , the introduction of psychology into the study of economic issues. 22 FRONTIERS OF MICROECONOMICS
第六章、第七章练习题 一、判断 1．某厂商产量达到5万时的MR=65元，MC=55元，（其它条件一定）该厂商应继续扩大产量. 2. 完全竞争厂商只能被动地接受既定的市场价格。 3. 完全竞争条件下，行业所面临的需求曲线是一条水平线。 4. 完全竞争厂商的短期供给曲线是短期边际成本曲线上等于和高于停止营业点的部分。 5. 完全竞争厂商的平均收益曲线和边际收益曲线与需求曲线是相同的。 6. 完全竞争厂商实现短期均衡时，定可获得大于零的经济利润。 7. 当一个完全竞争行业实现长期均衡时，每个企业都实现了正常利润，且经济利润都为零。 8. 在厂商短期均衡产量上，当AR＜SAC 且AR＞AVC时，厂商亏损，但应继续生产。 9. 在完全竞争市场上，SMC曲线和SAC 曲线的交点，被称为停止营业点。 10.垄断行业由于有规模经济可以比竞争行业产量更高，价格更低 11.完全竞争市场与垄断竞争市场的差别是后者可以影响产品的价格. 12.在完全竞争产品市场，厂商的短期反供给函数为P = SMC =f(Q)。 二、选择题 1、在完全竞争市场上，厂商短期均衡条件是（） A、P=AR B、P=MR C、P=MC D、P=AC 2、在垄断竞争中（） A、为数很少的厂商，有差异的产品 B、许多厂商，同质的产品； C、为数很少几个厂商，同质产品 D、许多厂商，有差异的产品 3、在一般情况下，厂商得到的价格若低于下述哪种成本，他将停止营业？（）A、平均可变成本 B、平均成本 C、平均不变成本 D、边际成本 4、在短期，完全垄断厂商（） A、无盈亏 B、取得最大利润 C、发生亏损 D、以上情况都可能出现 5、下列描述中，不属于完全垄断厂商实行差别定价的条件是（） A、市场存在不完全性 B、各个市场的需求弹性不同； C、市场未达到均衡状态 D、市场必须能有效地分离开来。 6、寡头垄断厂商的产品是（） A、同质的 B、有差异的 C、既可以是同质的，也可以是有差异的 D、以上都不对 7、P=MC的最大利润原则（） A．适用于任何条件下的厂商。 B、仅适用于完全竞争条件下的厂商。C．仅适用于非完全竞争的厂商。 D．所有的市场结构都不能适用。 8、在完全竞争市场上（） A、产品不同质 B、要素不能自由流动 C、信息不畅通 D、价格既定 9、在完全竞争市场的收支相抵点上（） A、P=SAC B、 P=LAC C、P=AVC D、MR=AVC 10、如果某厂商的平均收益曲线从水平线变为向右下方倾斜的曲线，说明（）。A、既有厂商进入也有厂商退出该行业 B、完全竞争被不完全竞争所取代 C、新的厂商进入了该行业 D、原有的厂商退出了该行业11、对一个垄断竞争企业来说，平均收益曲线（）。 A、和企业的需求曲线一样，边际收益曲线在企业的需求曲线之下。 B、在企业的需求曲线之上，边际收益曲线在企业的需求曲线之下。 C、在企业的需求曲线之上，边际收益曲线与企业的需求曲线相同。 D、和边际收益曲线一样都与企业的需求曲线相同。
一、名词解释（每小题5分，共50分） 1.机会成本 2.科斯定理 3.搭便车 4.囚徒困境 5.菲利普斯曲线 6.供应学派 7.凯恩斯革命 8.看不见的手 9.比较优势 10.外部性 二、简述题（第11、12、13题各12分，14题14分，共50分） 1.简述银行存款的创造过程。 2.简述失业的根源及其类型。 3.简述节俭的是非。 4.根据有关经济学原理，简析我国森林减少、珍稀动物来绝的原因及解决的措施。 三、论述题(每小题25分，共计50分) 1.论述人民币升值对中国经济的影响。 2.论述政府公共投资对国民经济的作用。 一、名词解释（每小题5分，共50分） 1.机会成本:指人们利用一定资源获得某种收入时所放弃的在其他可能的用途中所能够获取的最大收入。生产一单位的某种商品的机会成本是指生产者所放弃的使用相同的生产要素在其他生产用途中所能得到的最高收入。机会成本的存在需要三个前提条件。第一，资源是稀缺的；第二，资源具有多种生产用途；第三，资源的投
向不受限制。从机会成本的角度来考察生产过程时，厂商需要将生产要素投向收益最大的项目，而避免带来生产的浪费，达到资源配置的最优。机会成本的概念是以资源的稀缺性为前提提出的。从经济资源的稀缺性这一前提出发，当一个社会或一个企业用一定的经济资源生产一定数量的一种或者几种产品时，这些经济资源就不能同时被使用在其他的生产用途方面。这就是说，这个社会或这个企业所能获得的一定数量的产品收入，是以放弃用同样的经济资源来生产其他产品时所能获得的收入作为代价的。这也是机会成本产生的缘由。因此，社会生产某种产品的真正成本就是它不能生产另一些产品的代价。所以，机会成本的含义是：任何生产资源或生产要素一般都有多种不同的使用途径或机会，也就是说可以用于多种产品的生产。但是当一定量的某种资源用于生产甲种产品时，就不能同时用于生产乙种产品。因此生产甲种产品的真正成本就是不生产乙种产品的代价，或者是等于该种资源投放于乙种产品生产上可能获得的最大报酬。一种资源决定用于甲种产品，就牺牲了生产其他产品的机会；从事生产甲种产品的收入，是由于不从事或放弃其他产品生产的机会而产生的。 2.科斯定理:指一种产权理论。科斯本人并未将科斯定理写成文字，科斯定理的提出是由其好友斯蒂格勒首先根据科斯于20世纪60年代发表的《社会成本问题》这篇论文的内容概括出来的。其内容是：只要财产权是明确的，并且其交易成本为0或者很小，则无论在开始时财产权的配置是怎么样的，市场均衡的最终结果都是有效率的。科斯定理进一步扩大了“看不见的手”的作用。按照这个定理，只要那些假设条件成立，则外部影响就不可能导致资源配置不当。或者以另一角度来说，在所给条件下，市场力量足够强大，总能够使外部影响以最经济的办法来解决，从而仍然可以实现帕累托最优状态。西方学者认为，明确的财产权及其转让可以使得私人成本（或利益）与社会成本（或利益）趋于一致。以污染问题为例，科斯定理意味着，一旦所需条件均被满足，则污染者的私人边际成本曲线就会趋于上升，直到与边际社会成本曲线完全重合，从而污染者的利润最大化产量将下降至社会最优产量水平。 科斯定理解决外部影响问题在实际中并不—定真的有效。资产的财产权不一定总是能够明确地加以规定；已经明确的财产权不一定总是能够转让；分派产权会影响收入分配，而收入分配的变动可以造成社会不公平，引起社会动乱。在社会动乱的情况下，就谈不上解决外部效果的问题了。 3.搭便车：指不付成本或支付很低的成本而消费公共产品的行为。公共产品的特点决定了私人厂商不愿自动提供这种产品。这是因为在公用产品消费中存在“搭便车”问题，即每个人都想不付任何成本，或只支付很低的代价，来享受公共产品的服务。由于公共物品具有消费的非竞争性和受益的非排他性，人们可以在不付费的情况下享受公共物品所带来的效益。因此公共产品覆盖的消费者人数越多，搭便车问题就越严重，公共产品由私人厂商提供出来的可能性就越小。例如：1970年美国通用汽车公司研制出了一种汽车污染物排放控制装置，每个售价20美金，如果每个车尾都装上这一装置，可使汽车排放的污染下降30％至50％。然而，污染的降低是一种公共产品，每个人呼吸空气质量是否改善并不取决于自己的车上是否装上这个新发明，而是取决于该地区大多数车主的选择，于是大多数人都不想多花20美元而只是试图搭便车，结果，在私人市场上，这种公共产品的产量总难以达到最佳水平。私人不能提供公共产品，就只能由政府出面担当此项职能。事实上，私人经济中的政府，最初就是为了提供公共产品(法律、国防、公安等等)的目的由众多私人共同建立起来的。政府这一职能具体体现为：①尽可能正确地估价社会对公用产品的实际需求；②按照社会福利最大化的原则确定税收比率，并用税收收入购置公用产品，为公众提供服务。 4.囚徒困境：指两个被捕获的囚犯之间的一种特殊“博弈”，说明为什么甚至在合作对双方有利时，保持合作也是困难的。囚犯两难处境的故事包含着一个一般性的结论，这个结论适用于任何一个力图维持其成员合作的集团。这是博弈论中的一个经典例证，同一市场上的寡头在力图达到垄断结果时的博弈类似于两个处于两难处境的囚犯的博弈。具体情况如下：两囚徒被指控是一桩罪案的同案犯。他们被分关在不同的牢房且无法互通信息。各囚徒都被要求坦白罪行。如果两囚徒都坦白，各将被判入狱5年；如果两人都不坦白，则很难对他们提起刑事诉讼，因而两囚徒可以期望被从轻发落为入狱2年；另一方面，如果一个囚徒坦白而另一个囚徒不坦白，坦白的囚徒就只需入狱1年，而另一个将被判入狱10年。那么囚徒将会怎么选择呢？下表归纳了各种可能的结果。（其中“得益”是负的，表格右下角单元格意思是两个囚徒各2年徒刑）。该表说明，这两个囚徒面临着一种困境。如果他们都不坦白（以一种会遵守的方法），那么两人只需入狱仅仅2年。但他们不能相互讲话，如果囚徒A不坦白，他就冒着被B利用的危险。因为不管囚徒A怎么选择，囚徒B坦白总是最优方案。
第十二章税制的设计 复习题 1．在过去的几十年来，政府的增长比经济中的其他部分快还是慢? 答：在过去几十年间，政府的增长比经济中其他部分快。数据表明，美国经济中包括联邦、州和地方政府在内的政府收入在总收人中所占百分比的增长速度快于经济中其他部分。 2．美国联邦政府收入最重要的两个来源是什么? 答：美国联邦政府收入最重要的两个来源是个人收入所得税和用于社会保障的工薪税。 3．解释公司利润如何双重纳税。 答：当企业赚到利润时，它要按公司所得税交税；当企业用其利润向公司股东支付股息时，按个人所得税第二次交税。 4．为什么纳税人的税收负担大于政府得到的收入? 答：因为纳税人的税收负担除了向政府交纳的税收之外，还包括两种成本：一是税收改变了激励所引起的资源配置扭曲；二是遵守税法的管理负担。这两种成本没有政府的收入作为补偿。因此，纳税人的税收负担大于政府得到的收入。 5．为什么一些经济学家支持对消费征税，而不是对收入征税? 答：因为对收入征税扭曲了对人们储蓄的激励，鼓励人们少储蓄。如果政府采取消费税，储蓄起来的全部收入在最后支出前都不征税，就不会扭曲人们的储蓄决策。 6．举出富有的纳税人应该比贫穷纳税人多纳税的两种观点。 答：这方面的观点有受益原则和能力纳税原则。 受益原则认为：人们应该根据他们从政府服务中得到的利益来纳税。通常富人从公共服务中受益多，他们应该多纳税。 能力纳税原则认为：应该根据一个人所能承受的负担来对这个人征税。显然，富人的财务承受能力强于穷人，富人应该多纳税。 7．什么是横向平等概念。为什么运用这个概念是困难的? 答：横向平等是指主张有相似支付能力的纳税人应该缴纳等量税收的思想。这一原则面临的问题是什么决定两个纳税人是相似的。每个纳税人在许多方面不同，为了评价税收是不是横向平等，必须决定哪些差别对纳税人的支付能力是相关的，哪些是不相关的。这些相关关系的确定是复杂而困难的。它不仅涉及经济学问题，还涉及价值观问题，很难说确定的结果是否公平。 8．说明支持与反对用单一税率取代现行税制的观点。 答：单一税率的支持者认为：(1)单一税率税将取消现行所得税的许多税收减免。通过用这种方法扩大税基，固定税能够降低大多数人面临的边际税率。税率越低意味着经济福利越大。因此，单一税率支持者声称，这种改变将扩大经济馅饼的规模。(2)由于单一税率税如此简单，所以，赋税的管理负担将大大降低。(3)由于所有纳税人都面临相同的边际税率，所以可以按收入来源而不是按得到收入的人来收税。这种额外的简单化也降低了管理成本。 (4)单一税率税将取代个人所得税和公司所得税。所有收入无论是来自工作中的劳动还是来自公司中拥有的股份，都按相同的边际税率一次性纳税。单一税率将消除目前对公司利润的双重征税，这就可以鼓励企业投资于新工厂和设备。(5)在为纳税计算收入时，允许企业扣除所有合法的经营支出，包括新投资品的支出。这种投资扣除使单一税率税更像消费税而不像所得税。结果，变为单一税率税将提高对投资的激励。 单一税率税的反对者认为：这种税很少注意纵向平等的目标。他们声称，单一税率税的累进性要小于现在的税制，而且，特别是它会把一些税收负担从富人身上转移到中产阶级身上。
二十三章 1下列每种交易会影响CDP的哪一部分(如果有影响的话)?并解释之。 A．家庭购买了一台新冰箱。 答：家庭购买了一台新冰箱会增加GDP中的消费(C)部分，因为家庭用于家用电器的支出计算在消费的耐用品类中。 B．杰妮姑妈买了一所新房子。 答：杰妮姑妈买了一所新房子会增加GDP中的投资(1)部分，因为家庭住宅能长期供人居住，提供服务。它比一般耐用消费品的使用寿命更长，因此把住宅房屋的投资计算在投资中。 C.福特汽车公司由其存货中出售了一部雷鸟牌汽车。 答：福利汽车公司由其存货中出售了一部雷鸟牌汽车会减少现期GDP中的投资，因为销售中间物品存货时，企业的存货投资是负的，因而减少了当期的GDP。 C．你买了一个比萨饼。 答：我买了一个比萨饼会增加GDP中的消费(C)，因为我用于购买食品的支出计算在消费的非耐用品类中。 D．加利福尼亚重新铺设了101号高速公路。 答：加利福尼亚重新铺设了101号高速公路增加了GDP中的政府购买(G)，因为修建高速公路是政府的行为。 E．你的父母购买了一瓶法国红酒。 答：我的父母购买了一瓶法国红酒会减少GDP中的净出口(NX)，因为法国红酒是进口食品，它的购买增加了美国的进口。 F．本田公司扩大其在俄亥俄州马利斯维尔的工厂。 答：本田公司扩大其在俄亥俄州马利斯维尔的工厂增加了GDP中的净出口(NX)，因为本田公司是一家日本企业，它在美国的投资减少了美国对日本本田汽车的进口，使NX增加 2．GDP组成部分中的“政府购买”并不包括用于社会保障这类转移支付的支出。想想GDP 的定义，解释为什么转移支付不包括在政府购买内? 答：因为转移支付并不是要交换现在生产的物品或劳务，从宏观经济的角度看，转移支付就像税收和回扣一样。转移支付和税收一样改变了家庭收入，但并没有反映经济的生产。由于GDP是要衡量在某一既定时期一个国家从物品与劳务的生产中得到的收入，所以，不把转移支付包括在政府购买内。 6．考虑以下美国GDP的数据： A．1996年到1997年间名义收入增长率是多少?(注意：增长率是一个时期到下一个时期百分比的变动。 答：1996年到1997年间名义收入增长率是5．86%。 B．1996年到1997年间，GDP平减指数的增长率是多少? 答：1996年到1997年间，GDP平减指数的增长率是1．8%。 C．按1992年的价格衡量，1996年的实际GDP是多少? 答：按1992年的价格衡量，1996年的实际收入是69654．5亿元。 D．按1992年的价格衡量，1997年的实际GDP是多少? 答：按1992年的价格衡量，1997年的实际收入是72419．7亿元。