Presentation on theme: "In this chapter, you will learn:"— Presentation transcript:
03National Income in the Long Run : Where it Comes From and Where it Goes(edited by L. Lamb, 2011)The material in this chapter is the basis of much of the remaining material in this book. So, the time your students spend mastering this material will pay dividends throughout the semester.The 7th edition contains a new FYI box on the financial system and the crisis of I’ve added slides corresponding to this material.U P D A T E
1In this chapter, you will learn: 3.1 what determines the economy’s total output/income3.2 how the prices of the factors of production are determinedhow total income is distributed3.3 what determines the demand for goods and services3.4 how equilibrium in the goods market is achieved1
2Assumptions In chapters 3 to 6, we study the economy in the long run. We make the Classical assumptions for long run analysis.Classical assumptions: flexible prices (market clearing)I.e. quick adjustment of prices after a shock occurs (shift of curve)
33.1 What determines the Total Production of Goods & Services in the Long Run ? Factors of production K = capitalL = labour
4The production function shows how much output (Y ) the economy can produce from K units of capital and L units of laborreflects the economy’s level of technologyexhibits constant returns to scale
53.2 How is National Income Distributed to the Factors of Production determined by factor prices, the prices per unit firms pay for the factors of productionprice of L= _____________price of K = _____________
6How factor prices are determined Factor prices are determined by supply and demand in factor markets.
7Marginal product of labor (MPL ) definition: The extra output the firm can produce using an additional unit of labor (holding other inputs fixed)
8NOW YOU TRY: Compute & graph MPL L Y MPL0 0 n.a.1 10 ?2 19 ?3 27 84 34 ?5 40 ?6 45 ?7 49 ?8 52 ?9 54 ?10 55 ?a. Determine MPL at each value of L. b. Graph the production function. c. Graph the MPL curve with MPL on the vertical axis and L on the horizontal axis.
9NOW YOU TRY: MPL and labor demand L Y MPL0 0 n.a.2 19 93 27 84 34 75 40 66 45 57 49 48 52 39 54 2Suppose W/P = 6.If L = 3, should firm hire more or less labor? Why?If L = 7, should firm hire more or less labor? Why?
10The Neoclassical Theory of Distribution states that each factor input is paid its marginal producta good starting point for thinking about income distribution
11The Cobb Douglas Production Function The Cobb-Douglas production function is:where A represents the level of technology.
12Labor productivity and wages Theory: wages depend on labor productivityU.S. data:periodproductivity growthreal wage growth2.1%2.0%2.8%1.4%1.2%2.6%2.3%The table shows the average annual rates of productivity and real wage growth in each time period.Source: Economic Report of the President 2008and US Department of Commerce
133. 3 What Determines the Demand for Goods & Services 3.3 What Determines the Demand for Goods & Services? Demand for goods & servicesComponents of aggregate demand:C = consumer demand for g & sI = demand for investment goodsG = government demand for g & s(closed economy: no NX )
14The consumption function Y – TC (Y –T )The slope of the consumption function is the MPC.MPC1
15Investment, I The investment function is I = I (r ), where r denotes the real interest rate, the nominal interest rate corrected for inflation.
16Government spending, G G = govt spending on goods and services. G excludes transfer payments (e.g., social security benefits, unemployment insurance benefits).Assume government spending and total taxes are exogenous:
173.4 Equilibrium in the market for goods & services Summary of equations:Y = C + I + GC = C (Y-T)I = i(r)
18The loanable funds market A simple supply-demand model of the financial system.
19NOW YOU TRY: Calculate the change in saving Suppose MPC = 0.8 and MPL = 20.For each of the following, compute S :a. G = 100b. T = 100c. Y = 100d. L = 10
20The special role of rr adjusts to equilibrate the goods market and the loanable funds market simultaneously
21FYI: Markets, Intermediaries, the 2008 Crisis In the real world, firms have several options for raising funds they need for investment, including:borrow from bankssell bonds to saverssell shares of stock (ownership) to saversThe financial system includes:bond and stock markets, where savers directly provide funds to firms for investmentfinancial intermediaries, e.g. banks, insurance companies, mutual funds, where savers indirectly provide funds to firms for investmentThese slides correspond to a new FYI box on p.69. This material gives more detail about the financial system. While it ends with some information on the financial crisis, which will be explored in later chapters, the point here is that our loanable funds model, while abstracting from most of this detail, is fine for our present purposes.
22FYI: Markets, Intermediaries, the 2008 Crisis Intermediaries can help move funds to their most productive uses.But when intermediaries are involved, savers usually do not know what investments their funds are financing.Intermediaries were at the heart of the financial crisis of 2008….These slides correspond to a new FYI box on p.69. This material gives more detail about the financial system. While it ends with some information on the financial crisis, which will be explored in later chapters, the point here is that our loanable funds model, while abstracting from most of this detail, is fine for our present purposes.
23FYI: Markets, Intermediaries, the 2008 Crisis A few details on the financial crisis in the U.S.:July ’06 to Dec ’08: house prices fell 27%Jan ’08 to Dec ’08: 2.3 million foreclosuresMany banks, financial institutions holding mortgages or mortgage-backed securities driven to near bankruptcyCongress authorized $700 billion to help shore up financial institutionsSources:House price data is the Case-Shiller U.S. national home price index and Case-Shiller 20-city composite index, obtained from:Foreclosure data is from realtytrac.com,
24Chapter Summary Total output is determined by: the economy’s quantities of capital and laborthe level of technologyCompetitive firms hire each factor until its marginal product equals its price.If the production function has constant returns to scale, then labor income plus capital income equals total income (output).24
25Chapter Summary A closed economy’s output is used for: consumptioninvestmentgovernment spendingThe real interest rate adjusts to equate the demand for and supply of:goods and servicesloanable funds25
26Chapter SummaryA decrease in national saving causes the interest rate to rise and investment to fall.An increase in investment demand causes the interest rate to rise, but does not affect the equilibrium level of investment if the supply of loanable funds is fixed.26