宏观经济学曼昆(第五版)ch03

1、macroeconomics fifth editionN. Gregory MankiwPowerPoint Slides by Ron Cronovichmacro 2002 Worth Publishers, all rights reservedCHAPTER THREENational Income:Where it Comes From and Where it Goesslide 1what determines the economys total output/incomehow the prices of the factors of production are dete

2、rminedhow total income is distributedwhat determines the demand for goods and serviceshow equilibrium in the goods market is achievedslide 2A closed economy, market-clearing modelSupply sidefactor markets (supply, demand, price)determination of output/incomeDemand sidedeterminants of C, I, and GEqui

3、libriumgoods marketloanable funds marketslide 3K = capital, tools, machines, and structures used in productionL = labor, the physical and mental efforts of workersslide 4denoted Y = F (K, L)shows how much output (Y ) the economy can produce fromK units of capital and L units of labor. reflects the e

4、conomys level of technology. exhibits constant returns to scale.slide 5Initially Y1 = F (K1 , L1 ) Scale all inputs by the same factor z: K2 = zK1 and L2 = zL1 (If z = 1.25, then all inputs are increased by 25%)What happens to output, Y2 = F (K2 , L2 ) ? If constant returns to scale, Y2 = zY1 If inc

5、reasing returns to scale, Y2 zY1 If decreasing returns to scale, Y2 G , budget surplus = (T G ) = public saving When T 0big tax cuts: T 0According to our model, both policies reduce national saving:()SYC YTGGS TCS slide 49rS, I1SI (r )r1I1r22. which causes the real interest rate to riseI23. which re

6、duces the level of investment.1. The increase in the deficit reduces saving2Sslide 50variable1970s1980sT G2.23.9S19.617.4r1.16.3I19.919.4TG, S, and I are expressed as a percent of GDPAll figures are averages over the decade shown.slide 51Draw the diagram for the loanable funds model. Suppose the tax

7、 laws are altered to provide more incentives for private saving. What happens to the interest rate and investment? (Assume that T doesnt change)slide 522. Things that shift the investment curvea.certain technological innovations to take advantage of the innovation, firms must buy new investment good

8、sb.tax laws that affect investmentinvestment tax creditslide 53An increase in desired investmentrS, II1SI2r1r2raises the interest rate.But the equilibrium level of investment cannot increase because thesupply of loanable funds is fixed.slide 54Why might saving depend on r ?How would the results of a

9、n increase in investment demand be different?Would r rise as much?Would the equilibrium value of I change?slide 55Real interest rate, r2. . . raises the interest rate .Investment, Saving, I, SS(r)AB1. An increase in desired investment .3. . . and raises equilibrium investmentand saving.I2I1slide 561

10、.Total output is determined byhow much capital and labor the economy hasthe level of technology2.Competitive firms hire each factor until its marginal product equals its price. 3.If the production function has constant returns to scale, then labor income plus capital income equals total income (outp

11、ut).slide 574.The economys output is used forconsumption (which depends on disposable income)investment (depends on the real interest rate)government spending (exogenous)5.The real interest rate adjusts to equate the demand for and supply ofgoods and servicesloanable fundsslide 586.A decrease in national saving causes the interest rate to rise and investment to fa