经济学原理课后习题参考答案

在短期中，低通货膨胀通常是以高失业率为代价的，这是由短期内价格粘性造成的。政府为了抑制通货膨胀会减少流通中的货币量，人们可用的货币量减少,但商品价格在短期内具有粘性仍居高不下，于是社会消费的商品和劳务量减少，消费量不足又会引起企业开工不足，导致失业。失业率高，通胀率低;失业率低，通胀率高。通货膨胀和失业之间是此消彼长、相互交替的关系。

1.描述下列每种情形中当事人面对的权衡：

a.某个家庭决定是否购买一辆新车；a tradeoff between the cost of the car and other things they might want to buy.

b.国会成员决定对国家公园拨多少款the tradeoff is between parks and other spending items or tax cuts.（不增加拨款可少征税）

c.公司总裁决定是否建个新工厂；the decision is based on whether the new factory will increase the firm's profits compared to other alternatives. （upgrade existing equipment or expand existing factories）increase profit the most

d.某个教授决定用多少时间备课between the value of improving the qualityof the lecture compared to other things she could do with her time, such as working on additional research.

e.刚毕业的大学生决定是否读研究生

2.你正决定是否去度假。度假的大部分成本（机票、住宿费和放弃的工资）是用货币衡量

的，但度假的收益是心理上的。你如何比较度假的收益和成本？

two ways：pare the vacation with what you would do in its place。decide if you'd rather have the new clubs or the vacation.

2. think about how much work you had to do to earn the money to pay for the vacation

3.你正打算周六去做兼职，但你朋友让你去滑雪。去滑雪的真实成本是什么？现在假设你

本来打算周六在图书馆学习。在这种情形下，去滑雪的成本是什么？请解释。

its monetary and time costs, which includes the opportunity cost of the wages you are giving up by not working.

4.你在篮球比赛博彩中赢了100 元。对于这笔钱你有两个选择，你可以现在就花掉或者存

入银行，银行利率为5%，你现在就将这笔钱花掉的机会成本是多大？

you are giving up the opportunity to spend $105 a year from now.

5.你管理的公司已经投资500 万元开发某个新产品，但研发尚未结束。在最近一次会议上，

销售人员向你报告说由于竞争产品上市，该产品的期望销售额下降为300 万元。如果你还需

要再投入100 万元才能完成该产品的研发，你会继续下去吗？为了完成研发，你最多愿意支

付多杀钱？

$5 million is the sunk cost. 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.

In fact, you'd pay up to $3 million；any more than that, and you won't be increasing profit at the margin.

6.社会保障系统为年龄超过65 岁的老人提供收入。如果接受救济的某个老人决定去工作

以争取部分收入，那么他从社会保障得到的钱数通常就会减少。

a.提供社会保障对人们在工作期间（年轻时）的储蓄激励有何影响？

lowers an individual’s incentive to save for retirement.

The benefits provide some level of income to the individual when he or she retires.

individual is not entirely dependent on savings to support consumption through the years in retirement.

b.收入较高时保障金会下降，这对65 岁以上老人的工作激励有何影响？

an incentive not to work (or not work as much) after age 65.

Because the more you work, the lower your after-tax Social Security benefits will be.

7.某法案于1996 年实施，它对美国联邦政府反困项目进行了改革，新法案规定某些被

救助者只能领取两年的救济金。

a.这种改革对穷人的工作激励有何影响？

they have greater incentive to find jobs

b.这种改革对平等和效率之间的权衡有何影响（更侧重于效率还是平等）？

the change in the law is one that increases efficiency but reduces equity.

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.

8.你的室友做得饭菜比你好吃，但你打扫卫生的速度比他快。如果你的室友只做饭而你只打扫卫生，这比你们各干各的家务花费更多还是更少时间？再举一个类似的例子说明专业化和贸易如何使两个国家的状况更好。

By specializing, you reduce the total time spent on chores.（家庭杂务）

countries can specialize and trade, making both better off.

EX. make clothes and make wine efficiently s produce all the clothes and French workers produce all the wine, and they exchange some wine for some clothes.

9.解释下列每一项政府行为的出发点是更关注平等还是更关注效率。如果是更关注效率，分析可能涉及的市场失灵情形。

a.管制有线电视价格；

b.为某些穷人提供购买食品时可做钱使用的食品券；

c.在公共场所禁止吸烟；

d.将标准石油公司（该石油公司一度拥有美国90%的炼油厂）拆分成几家小公司；

e.对高收入人群征收较高的个人所得税；

f.颁布法律禁止酒后开车

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