复习题：

1. What is the role of the financial system? Name and describe two markets that are part of the financial system in our economy. Name and describe two
financial intermediaries.

答：金融体系是将储蓄和投资匹配起来。 金融系统的两个市场是债券市场，通过这个市场，大公司，联邦政府、州政府和地方政府借钱。另外一个市场就是股票市场，公司通过这个市场出售他们的股份。 两种金融媒介是银行，吸收存款和放贷。另外一个金融媒介是共同基金，通过对公众出售其股份用得到的钱去组合投资金融资产。

2. Why is it important for people who own stocks and bonds to diversify their holdings? What type of financial institution makes diversification easier?

答：分散投资，减少风险。

    共同基金是好的方式。

3. What is national saving国民储蓄? What is private saving私人储蓄? What is public saving公共储蓄? How are these three variables related?

答：私人储蓄是家庭去除税收和消费支出后剩余部分。公共储蓄是政府税收除去其支出后剩余部分。国民储蓄=私人储蓄+公共储蓄。

4. What is investment? How is it related to national saving?

答：投资就是添置新资本，如设备、建筑。投资等于国民储蓄。

5. Describe a change in the tax code that might increase private saving. If this policy were implemented, how would it affect the market for loanable funds?

答：用消费税代替收入税，会促进私人储蓄。因为可贷资金增加，导致贷款利率下降，导致投资增加。

6. What is a government budget deficit? How does it affect interest rates, investment, and economic growth?

答：政府预算赤字就是政府收税不抵其支出。政府赤字减少了国民储蓄，导致利率太高，减少了个人投资，降低了经济增长。

应用题：

1. For each of the following pairs, which bond would you expect to pay a higher interest rate? Explain.
a. a bond of the U.S. government or a bond of an eastern European government

答：美国政府债券所给利息少，东欧国家政府债券利息高，因为高风险，高收益。

b. a bond that repays the principal 偿还本金in 2005 or a bond that repays the principal in 2025

答：2025年偿还本金债券利息高，因为期限越长，风险越大。

c. a bond from Coca-Cola or a bond from a software company you run in your garage

答：可口可乐公司的债券比在你家车库经营软件公司的债券利率低，因为该软件公司的信用风险低。

d. a bond issued by the federal government or a bond issued by New York State

答：联邦政府债券利率高，因为要交联邦收入税。

2. Look up in a newspaper the stock of two companies you know something about (perhaps as a customer). What is the price–earnings ratio for each company? Why do you think they differ? If you were to buy one of these stocks, which would you choose? Why?

答：Many answers are possible.  Price-earnings ratios vary.  A high price-earnings ratio might indicate either that people expect earnings to rise in the future or that the stock is overvalued.  A low price-earnings ratio might indicate either that people expect earnings to fall or that the stock is undervalued. 高的市盈率表示这支股票前景看好或者股价过高。低的市盈率表示该股票前景暗淡或估价过低。

3. Theodore Roosevelt 西奥多-罗斯福 once said, “There is no moral difference between gambling at cards or in lotteries or on the race track and gambling in the stock market.” What social purpose do you think is served by the existence of the stock market?

答：有社会目的。因为公司可以通过发行股票得到资金。而人们偏爱股票而不是扑克赌博，是因为这是一个有组织的市场，当人们想卖掉股票时，可以卖掉。
4. Use the Internet to look at the Web site for a mutual fund company, such as Vanguard (www.vanguard.com). Compare the return on an actively managed mutual
fund with the return on an index fund. What explains the difference in these returns?

答：略。
5. Declines in stock prices are sometimes viewed as harbingers of future declines in real GDP. Why do you suppose that might be true?

答： 人们对股票的评价基于股票的将来盈利性。如果股票价格下跌，说明人们对公司盈利前景不看好。这就意味着公司的将来产出减少。

6. When the Russian government defaulted on its debt to foreigners in 1998, interest rates rose on bonds issued by many other developing countries. Why do you suppose this happened?

答：当俄罗斯拖欠贷款，投资者觉察到其他发展中国家也有可能拖欠贷款，所以可供贷款量减少，贷款利率上升。

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7. Many workers hold large amounts of stock issued by the firms at which they work. Why do you suppose companies encourage this behavior? Why might a person not want to hold stock in the company where he works?

答：公司鼓励职工持股，这样激励职工关心公司利润，不只是他们的工资。这样职工看到浪费或需要改善之处，就会采取行动。也会鼓励职工努力工作。

     但是从雇员角度看，持有本公司股票可能风险很大。因为雇员工资已经和公司经营业绩联系起来了。如果公司经营出现问题，可能被解雇或减薪。如果同时持有本公司股票，其股票也将贬值，所以为了分散风险，雇员愿意持有其他公司股票。

8. Your roommate says that he buys stock only in companies that everyone believes will experience big increases in profits in the future. How do you suppose
the price–earnings ratio of these companies compares to the price–earnings ratio of other companies? What might be the disadvantage of buying stock in these
companies?

答：略
9. Explain the difference between saving and investment as defined by a macroeconomist. Which of the following situations represent investment? Saving? Explain.

答：对宏观经济学家而言，当一个人收入超过其消费，储蓄就发生了。当一个人或公司购买新资本，如房子或生意设施，投资就发生了。

a. Your family takes out a mortgage and buys a new house.抵押贷款

答：投资
b. You use your $200 paycheck工资 to buy stock in AT&T.

答：储蓄，因为收入没有用于消费产品。
c. Your roommate earns $100 and deposits it in her account at a bank.

答：储蓄。
d. You borrow $1,000 from a bank to buy a car to use in your pizza delivery business.

答：投资。

10. Suppose GDP is $8 trillion, taxes are $1.5 trillion, private saving is $0.5 trillion, and public saving is $0.2 trillion. Assuming this economy is closed, calculate consumption, government purchases, national saving, and investment.GDP8万亿，税收1.5万亿，个人储蓄0.5万亿，公共储蓄 0.2万亿。经济是封闭的。计算消费，政府购买，国民储蓄和投资。

答：

Given that Y = 8, T = 1.5, S_private = 0.5 = Y - T - C, S_public = 0.2 = T - G.

            Since S_private = Y - T - C, then rearranging gives C = Y - T - S_private = 8 - 1.5 - 0.5 = 6.  Since S_public = T - G, then rearranging gives G = T - S_public = 1.5 - 0.2 = 1.3.

Since S = national saving = S_private + S_public = 0.5 + 0.2 = 0.7.

Finally, since I = investment = S, I = 0.7.

个人储蓄=GDP-税收-消费，所以消费=GDP-税收-个人储蓄=8-1.5-0.5=6

公共储蓄=税收-政府购买，政府购买=税收-公共储蓄=1.5-0.2=1.3

国民储蓄=公共储蓄+个人储蓄=0.5+0.2=0.7

投资=国民储蓄=0.7

注意，以上结论仅限于封闭经济。
11. Suppose that Intel is considering building a new chipmaking factory.
a. Assuming that Intel needs to borrow money in the bond market, why would an increase in interest rates affect Intel’s decision about whether to build
the factory?

答： 如果利率增加，借钱建造新工厂的成本高了，这样建造新工厂的汇报可能无法弥补这个成本。高利率的结果，可能是因特尔放弃建造新工厂。
b. If Intel has enough of its own funds to finance the new factory without borrowing, would an increase in interest rates still affect Intel’s decision about whether to build the factory? Explain.

答：即使因特尔有足够的自有资金来建新厂房，利率提高同样对其有影响。因特尔可以把这些钱投放到债券市场得到较高的利息。因特尔将比较盖新厂房和投放到债券市场哪个回报更高。这样，同样因特尔可能不愿投资建新厂房。

12. Suppose the government borrows $20 billion more next year than this year.
a. Use a supply-and-demand diagram to analyze this policy. Does the interest rate rise or fall?

答：

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如图，美国政府增加举债，导致利率上升。

b. What happens to investment? To private saving? To public saving? To national saving? Compare the size of the changes to the $20 billion of extra government borrowing.

答：因为利息增加，投资和国民储蓄下降而个人储蓄上升。政府举债减少了公共储蓄。从图上可以看出，可贷资金总量减少小于20百万，公共储蓄减少20百万，而个人储蓄增加小于20百万。
c. How does the elasticity of supply of loanable funds affect the size of these changes? (Hint: See Chapter 5 to review the definition of elasticity.)

答：

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供应弹性越大，利率增加越小。
d. How does the elasticity of demand for loanable funds affect the size of these changes?

答：

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需求弹性越大，利率上升越小。
e. Suppose households believe that greater government borrowing today implies higher taxes to pay off the government debt in the future. What does this belief do to private saving and the supply of loanable funds today? Does it increase
or decrease the effects you discussed in parts (a) and (b)?

答：  如果家庭相信，政府大量举债导致将来税负提高，未雨绸缪，家庭将增加个人储蓄，可贷资金数量增加。这样将抵消部分公共储蓄减少影响，减少了均衡可贷资金数量的下降幅度，降低了利率上升幅度。

     如果个人储蓄增加正好等于政府借债增加，一切都不会改变，包括投资、国民储蓄和利率。

 
13. Over the past ten years, new computer technology has enabled firms to reduce substantially the amount of inventories they hold for each dollar of sales. Illustrate the effect of this change on the market for loanable funds. (Hint: Expenditure on inventories is a type of investment.) What do you think has been the effect on investment in factories and equipment? 过去10年间，新的电脑技术使企业每卖出1美元产品的存货量大大减少。说明这种变化对可贷资金市场的影响。（提示，存货是投资）。你认为对工厂设备的投资有影响吗？

答： 存货需求减少，导致资金需求曲线左移，均衡可贷资金数量下降，利率下降。利率下降导致工厂设备投资增加。

14. “Some economists worry that the aging populations of industrial countries are going to start running down their savings just when the investment appetite of
emerging economies is growing” (Economist, May 6, 1995). Illustrate the effect of these phenomena on the world market for loanable funds. 经济学家担心，正当新出现的经济投资胃口增长时，工业化国家人口老龄化开始消耗其储蓄。说明这种现象对可贷资金市场的影响。

答：均衡利率肯定增加，均衡量难说。如下图。

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15. This chapter explains that investment can be increased both by reducing taxes on private saving and by reducing the government budget deficit.本章介绍了对个人储蓄减税会导致投资增加，减少政府赤字也会导致投资增加。
a. Why is it difficult to implement both of these policies at the same time?

答：同时执行这两项政策是困难的，因为减税导致赤字增加，除非有其他税收收入或削减政府开支。
b. What would you need to know about private saving in order to judge which of these two policies would be a more effective way to raise investment?为了判断这两种政策中哪种更有效，你需要对储蓄了解什么？

答：(1) 个人储蓄弹性大小，因为它决定了减税对增储的效果(2) 个人储蓄对政府财政赤字的反应 (3) 投资对利率的弹性，如果投资没有弹性，什么政策都不会增加投资。