宏观经济学 曼昆(第五版)ch03.ppt

In this chapter you will learn: what determines the economy’s total output/income how the prices of the factors of production are determined how total income is distributed what determines the demand for goods and services how equilibrium in the goods market is achieved Outline of model A closed economy, market-clearing model Supply side factor markets (supply, demand, price) determination of output/income Demand side determinants of C, I, and G Equilibrium goods market loanable funds market Factors of production K = capital, tools, machines, and structures used in production L = labor, the physical and mental efforts of workers The production function denoted Y = F (K, L) shows how much output (Y ) the economy can produce fromK units of capital and L units of labor. reflects the economy’s level of technology. exhibits constant returns to scale. Returns to scale: a review Initially 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 increasing returns to scale, Y2 zY1 If decreasing returns to scale, Y2 zY1 Exercise: determine returns to scale Determine whether each of the following production functions has constant, increasing, or decreasing returns to scale: Assumptions of the model Technology is fixed. The economy’s supplies of capital and labor are fixed at Determining GDP Output is determined by the fixed factor supplies and the fixed state of technology: The distribution of national income determined by factor prices, the prices per unit that firms pay for the factors of production. The wage is the price of L , the rental rate is the price of K. Notation W = nominal wage R = nominal rental rate P = price of output W /P = real wage  (measured in units of output) R /P = real rental rate How factor prices are determined Factor pric