中级宏观经济学(Macroeconomics)考试试题答案

中级宏观经济学（Macroeconomics）考试试题答案

(经济试验班021、022)

Ⅰ.Choose the best answers (2＇×10)

1.B 2.A 3.C 4.B 5.C 6.A 7.B 8.C 9.C 10.D

Ⅱ. Explain the following terms. (20 points)

1．Endogenous variables: 经济模型中要解释的变量。

Exogenous variables：模型给出作为既定的变量。 2. Menu costs：企业因通货膨胀改变价格的成本。

shoe-leather costs：为减少持有货币的损失而发生的成本。

3. GDP deflator ：名义GDP/实际GDP，是相对于基年商品和劳务价格的那一年的商品和劳务价格。

CPI：即消费价格指数，是相对于某个基年一篮子物品与劳务价格的同样一篮子物品与劳务的现期价格。

4. Adaptive expectation ：人们根据过去的经验或数据来预测未来。

rational expectation：人们尽可能地利用所有可以获得地信息，包括关于现在政府政策地信息预测未来。

5. Real exchange rate ：两国物品的相对价格。 nominal exchange rate：两国通货的相对价格。

Ⅲ. Answer the following questions by drawing or calculating. (10’ ×4) 1．We want to consider the effects of a tax cut when the LM* curve depends on disposable income instead of income: M/P = L[r, Y – T].

A tax cut now shifts both the IS* and the LM* curves. Figure 12–22 shows the case of floating exchange rates. The IS* curve shifts to the right, from IS to IS . The LM* curve shifts to the left, however, from LM to LM .

We know that real balances M/P are fixed in the short run, while the interest rate is fixed at the level of the world interest rate r*. Disposable income is the only variable that can adjust to bring the money market into equilibrium: hence, the LM* equation determines the level of disposable income. If taxes T fall, then income Y must also fall to keep disposable income fixed. In Figure 12–22, we move from an original

equilibrium at point A to a new equilibrium at point B. Income falls by the amount of the tax cut, and the exchange rate appreciates. If there are fixed exchange rates, the IS* curve still shifts to the right; but the initial shift in the LM* curve no longer

matters. That is, the upward pressure on the exchange rate causes the central bank to sell dollars and buy foreign exchange; this increases the money supply and shifts the LM* curve to the right, as shown in Figure 12–23. The new equilibrium, at point B, is at the intersection of the new IS* curve, IS , and the horizontal line at the level of the fixed exchange rate. There is no difference between this case and the standard case where money demand depends on income.

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2. a.将生产函数两边同时除以效率工人，则有：

YK0.4EL0.6KyELELEL0.4k0.4

b．s=0.25 δ=5% n=2% g=3%; 带入经济稳定的条件：

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sf(k)(ng)k0.25k0.40.1kk*2.55/34.6y*k0.42.52/31.84c*(1s)y0.752.52/31.38 c.当g变为5%时，有：

sf(k)(ng)k0.25k0.40.12k25 k*12y*k0.45/33.42/3

25121.63这种变化导致了效率工人的人均资本量减少，效率工人的人均产量下降；但总产出会增加。

3.The aggregate demand curve represents the negative relationship between the price level and the level of national income. In Chapter 9, we looked at a simplified theory of aggregate demand based on the quantity theory. In this chapter, we explore how the IS–LM model provides a more complete theory of aggregate demand. We can see why the aggregate demand curve slopes downward by considering what happens in the IS–LM model when the price level changes. As Figure 11–1(A) illustrates, for a given money supply, an increase in the price level from P1 to P2 shifts the LM curve upward because real balances decline; this reduces income from Y1 to Y2. The

aggregate demand curve in Figure 11–1(B) summarizes this relationship between the price level and income that results from the IS–LM model.

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4.a. Recall from Chapter 4 that we can express the quantity equation in terms of percentage changes: %in M + %in V = %in P + %in Y.

If we assume that velocity is constant, then the %in V = 0. Therefore, %in M = %in P + %in Y.

We know that in the short run, the price level is fixed. This implies that the %in P = 0. Therefore,

%in M = %in Y.

Based on this equation, we conclude that in the short run a 5-percent reduction in the money supply leads to a 5-percent reduction in output. This is shown in Figure9-9. In the long run we know that prices are flexible and the economy returns to its natural rate of output. This implies that in the long run, the %in Y = 0. Therefore, %in M = %in P. Based on this equation, we conclude that in the long run a 5-percent reduction in the money supply leads to a 5-percent reduction in the price level, as shown in Figure 9–9.

b.Okun’s law refers to the negative relationship that exists between unemployment and real GDP. Okun’s law can be summarized by the equation:

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%in Real GDP = 3% – 2 [in Unemployment Rate]. That is, output moves in the opposite direction from unemployment, with a ratio of 2 to 1. In the short run, when Y falls 5 percent, unemployment increases 2-1/2 percent. In the long run, both output and unemployment return to their natural rate levels. Thus, there is no long-run change in nemployment.

Ⅳ. Use the theories that you just have learnt to analysis the macroeconomics policies in china and give your suggestions. (20＇×1)

略

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