对外经济贸易大学经济学论通用讲义十对外经济贸易大学经济学导论通用讲义十.ppt

总需求与总供给 23 本章我们将探索这些问题的答案： 什么是经济波动？它们的特点是什么？ 总需求与总供给模型如何解释经济波动？ 为什么总需求曲线向右下方倾斜？什么使总需求曲线移动？ 短期总供给曲线的斜率是多少？长期的呢？什么使总供给曲线移动？ 货币政策和财政政策对总需求的影响 24 本章我们将探索这些问题的答案： 利率效应如何帮助我们解释总需求曲线的斜率？ 中央银行如何使用货币政策来移动总需求曲线？ 财政政策通过哪两条途径来影响总需求？ 支持和反对使用政策来稳定经济的理由分别是什么？ * A change in P won’t shift the AD curve, but will cause a movement along the AD curve. * The slope of the AS curve depends on the time horizon: In the short run, the aggregate supply curve is upward-sloping. (“SR” = “short run”). In the long run, the aggregate supply curve is vertical. These slopes will be explained in the following slides. * The book does not use the notation YN. I use it here to keep the slides from getting too cluttered, and also to make it easier for students to take notes: it’s easier for them to write “YN” than “the natural rate of output.” * This is review from the chapter “Production and Growth.” * It might be worth mentioning that the change in weather patterns or reduction in imported resources would have to be reasonably long-lasting for the LRAS curve to shift. Short-lived changes are more likely to affect SRAS than LRAS. * In the following chapter, it will be more clear why money supply growth shifts the AD curve rightward. * Before introducing the three theories of short-run aggregate supply, it’s worth taking a moment to show students why the slope of SRAS is critically important in the theory of economic fluctuations. * Each of these theories provides a reason why the aggregate supply curve might have a positive slope in the short run. It would be most helpful if students carefully read this section of the chapter! * “If P PE” means “If the actual price level turns out to be higher the price level firms had expected...” * Of the three theories, this one seems the least plausible. Firms certainly have a strong incentive to not mistake a general price increase for a relative price increase. And information about the price level is costless and available with on