宏观经济学Investment参考.pptVIP

Investment In this chapter, you will learn… 解释每一类型投资的主要理论。 why investment is negatively related to the interest rate为什么投资与利息率是负相关的 things that shift the investment function投资函数移动的因素 why investment rises during booms and falls during recessions为什么在经济繁荣时期投资上升，在经济衰退时期投资会下降。 Three types of investment Business fixed investment固定资产投资:businesses’ spending on equipment and structures for use in production. Residential investment居住投资:purchases of new housing units (either by occupants or landlords). Inventory investment存货投资:the value of the change in inventories of finished goods, materials and supplies, and work in progress. U.S. investment and its components Understanding business fixed investment 固定资产投资的标准模型The standard model of business fixed investment: the neoclassical model of investment 表明投资取决于 MPK interest rate tax rules affecting firms Two types of firms For simplicity, 假定有两种类型: 1. Production firms rent the capital they use to produce goods and services.租用资本来生产商品和服务。 2. Rental firms own capital, rent it to production firms.拥有资本，将资本出租给生产企业 The capital rental market Factors that affect the rental price Rental firms’ investment decisions Rental firms invest in new capital when the benefit of doing so exceeds the cost当投资新资本品的收益大于成本时，租赁企业会投资新资本. The benefit (per unit capital): R/P, the income that rental firms earn from renting the unit of capital to production firms租赁企业将一单位资本品租给生产企业所赚得的收入。 The cost of capital Components of the cost of capital资本品成本的内容: interest cost: i ?PK, where PK = nominal price of capital depreciation cost: ? ?PK, where ? = rate of depreciation capital loss: ? ?PK  (a capital gain, ?PK 0, reduces cost of K ) The total cost of capital is the sum of these three parts: The cost of capital Example: car rental company (capital: cars) 假定 PK = $10,000, i = 0.10, ? = 0.20,  and ?PK/PK = 0.06 The cost of capital For simplicity, 假定 ?PK/PK = ?. 整体通货膨胀率 Then, the nominal cost of capital equals PK(i + ? ? ?) = PK(r