曼昆《宏觀經(jīng)濟(jì)學(xué)（第七版）》課題習(xí)題參考答案

1、Answers to Textbook Questions and ProblemsQuestions for Review Questions for Review1. Microeconomics is the study of how individual firms and households make decisions, and how they interact with one another. Microecono

2、mic models of firms and households are based on principles of optimization—firms and households do the best they can given the constraints they face. For example, households choose which goods to pur- chase in order to

3、maximize their utility, whereas firms decide how much to produce in order to maximize profits. In contrast, macroeconomics is the study of the economy as a whole; it focuses on issues such as how total output, total empl

4、oyment, and the overall price level are determined. These economy-wide variables are based on the interaction of many households and many firms; therefore, microeconomics forms the basis for macroeconomics.2. Economist

5、s build models as a means of summarizing the relationships among economic variables. Models are useful because they abstract from the many details in the econo- my and allow one to focus on the most important economic co

6、nnections.3. A market-clearing model is one in which prices adjust to equilibrate supply and demand. Market-clearing models are useful in situations where prices are flexible. Yet in many situations, flexible prices ma

7、y not be a realistic assumption. For example, labor contracts often set wages for up to three years. Or, firms such as magazine pub- lishers change their prices only every three to four years. Most macroeconomists beli

8、eve that price flexibility is a reasonable assumption for studying long-run issues. Over the long run, prices respond to changes in demand or supply, even though in the short run they may be slow to adjust.Problems and

9、Applications Problems and Applications1. Most of the macroeconomic issues that have been in the news lately (early 2009) are related to the worsening recession that officially began in December of 2007. The econ- omy h

10、as not seen a recession like this since the back-to-back recessions of 1980–1982. Noteworthy topics would be an unemployment rate that hit 8.1% in February 2009, a rising saving rate, an inflation rate that is near zero

11、, output growth that was –6.3% in the fourth quarter of 2008, the ongoing financial and housing market crises, and news about the stimulus package designed to help the economy recover more quickly.2. Many philosophers o

12、f science believe that the defining characteristic of a science is the use of the scientific method of inquiry to establish stable relationships. Scientists examine data, often provided by controlled experiments, to su

13、pport or disprove a hypothesis. Economists are more limited in their use of experiments. They cannot con- duct controlled experiments on the economy; they must rely on the natural course of developments in the economy

14、to collect data. To the extent that economists use the sci- entific method of inquiry, that is, developing hypotheses and testing them, economics has the characteristics of a science.3. We can use a simple variant of th

15、e supply-and-demand model for pizza to answer this question. Assume that the quantity of ice cream demanded depends not only on the price of ice cream and income, but also on the price of frozen yogurt:Q d = D(PIC, PFY,