劳动经济学英语PPTPPT文件格式下载.ppt

1、Next pageCopyright 2008 by The McGraw-Hill Companies,Inc.All rights reserved.McGraw-Hill/IrwinChapter 5The Demand for LaborJump to first page5-5-2 21.Derived Demand for LaborJump to first page5-5-3 3The demand for labor is a derived demand.That is,it is derived from the demand for the product or ser

2、vice that the labor is helping produce.The demand for hamburgers leads to the demand for hamburger workers.Demand for workers depends on:#How the productive the workers are.The price of the product the workers are helping produceDerived DemandJump to first page5-5-4 42.A Firms Short-Run Production F

3、unctionJump to first page5-5-5 5A production function shows the relationship between inputs and outputs.Assume that only two inputs are used to make a product-labor（L）and capital（K）.In the short run,at least one input is fixed.The total product for a firm in the short run is:#TPSR=f（K,L）,where K is

4、fixed.Production FunctionJump to first page5-5-6 6Total product（TP）is the total product produced by each combination of labor and the fixed amount of capital.Marginal product（MP）is the change in total product associated with the addition of one more unit of labor.Average product（AP）is the total prod

5、uct divided by the number of units of labor.DefinitionsJump to first page5-5-7 7Total Product 0 TotalProduct54321 As units of variable input（labor）are added to a fixed input,total product will increase.20304050607080106780910AverageProductMarginalProductTotalProduct（Output）Units of Variable Resource

6、 18 220 334 446 556 664 770 874 975 1073 First at an increasing rate.Then at a declining rate.Note that the Total Product curve is smooth,indicating that labor can be increased by amounts of less than a single unit（it is a continuous function）.Quantity of LaborLaw of Diminishing ReturnsLaw of Dimini

7、shing ReturnsJump to first page5-5-8 8Average ProductMarginal Product 0 Average and/or Marginal Product54321 The Marginal Product curve will initially increase（when TPC is increasing at an increasing rate）,reach a maximum,and then decrease（as TPC increases at a decreasing rate）.4812166780910AverageP

8、roductMarginalProductTotalProduct（Output）Units of Variable Resource 18 220 334 446 556 664 770 874 975 1073-812141210 8 6 4 1-2-81011.311.511.210.7109.38.37.3 The Average Product curve will have the same general form except that its maximum point will be at a higher output level.Important Note:#MP a

9、lways crosses AP at its maximum point.Quantity of LaborLaw of Diminishing ReturnsLaw of Diminishing ReturnsJump to first page5-5-9 9Average ProductMarginal ProductAP&#MPQuantity of Labor543214812166 7 8 9 10Total ProductTP5432120304050607080106 7 8 9 10Quantity of Labor Graphed together,one can see

10、the relationship between the TP,MP,and AP curves more clearly.Law of Diminishing ReturnsJump to first page5-5-10103.Short-Run Demand for Labor:#The Perfectly Competitive SellerJump to first page5-5-1111Marginal revenue product（MRP）is the change in total revenue that results from hiring of an additio

11、nal worker.MRP=Marginal Revenue（MR）*MPProfit-maximizing firms will hire additional workers as long as each worker adds more to revenue than she costs.Hiring DecisionJump to first page5-5-1212Marginal wage cost（MWC）is the change in total wage cost of hiring an additional worker.The Hiring Rule:#Hire

12、additional workers until MRP=MWC.Hiring DecisionJump to first page5-5-1313MP TP L（3）TotalProduct（TP）（units per week）（2）Units of Labor（L）（1）Sales Price（Per Unit）（4）TotalRevenue（5）0.0 5.0 9.0 12.014.0 15.516.517.05.0$1,0004.0$1,8003.0$2,4002.0$2,8001.5$3,1001.0$3,3000.5$3,400-$0 1000 800 600 400 300 2

13、00 100-In the numerical example below,a computer company uses both technology and data-entry operators to provide services in a perfectly competitive market.For each unit processed the firm receives$200（4）.Short-Run Demand for Perfectly Competitive Firm Column（2）shows how total output changes as add

14、itional data-entry operators are hired（given a fixed capital level）.The Marginal Revenue Product schedule（6）indicates how hiring an additional operator affects the total revenue of the firm.0 1 2 3 4 5 6 7$200$200$200$200$200$200$200$200MRP TR L（6）Jump to first page5-5-1414 Since a profit-maximizing

15、 firm will only hire an additional worker only if the worker adds more to revenues than she adds to wage costs,the MRP curve is the firms short run demand curve for labor.Wage RateQuantity of Labor1000Short-Run Labor Demand8006004002001234567 In the short-run,it will slope downward because the margi

16、nal product of labor falls as more of it is used with a fixed amount of capital.MRP=DLJump to first page5-5-1515The value of marginal product（VMP）is the extra output in dollar terms that society gains when an extra worker is employed.VMP=Price*MPFor a perfectly competitive seller,MR=Price.As a result,VMP=MRP for such firms.Value of Marginal ProductJump to first page5-5-16161.“Only that portion of the MP curve that lies below AP constitutes the basis for a firms short-run demand curve for labor.”Explai