微观经济学production(编辑修改稿)

微观经济学production(编辑修改稿)内容摘要：

ons 169。 2020 Pearson Education, Inc. Chapter 6 39 Production: Two Variable Inputs Firm can produce output by bining different amounts of labor and capital In the long run, capital and labor are both variable We can look at the output we can achieve with different binations of capital and labor – Table 169。 2020 Pearson Education, Inc. Chapter 6 40 Production: Two Variable Inputs 169。 2020 Pearson Education, Inc. Chapter 6 41 Production: Two Variable Inputs The information can be represented graphically using isoquants Curves showing all possible binations of inputs that yield the same output Curves are smooth to allow for use of fractional inputs Curve 1 shows all possible binations of labor and capital that will produce 55 units of output 169。 2020 Pearson Education, Inc. Chapter 6 42 Isoquant Map Labor per year 1 2 3 4 5 Ex: 55 units of output can be produced with 3K amp。 1L (pt. A) OR 1K amp。 3L (pt. D) q1 = 55 q2 = 75 q3 = 90 1 2 3 4 5 Capital per year D E A B C 169。 2020 Pearson Education, Inc. Chapter 6 43 Production: Two Variable Inputs Diminishing Returns to Labor with Isoquants Holding capital at 3 and increasing labor from 0 to 1 to 2 to 3 Output increases at a decreasing rate (0, 55, 20, 15) illustrating diminishing marginal returns from labor in the short run and long run 169。 2020 Pearson Education, Inc. Chapter 6 44 Production: Two Variable Inputs Diminishing Returns to Capital with Isoquants Holding labor constant at 3 increasing capital from 0 to 1 to 2 to 3 Output increases at a decreasing rate (0, 55, 20, 15) due to diminishing returns from capital in short run and long run 169。 2020 Pearson Education, Inc. Chapter 6 45 Diminishing Returns Labor per year 1 2 3 4 5 Increasing labor holding capital constant (A, B, C) OR Increasing capital holding labor constant (E, D, C q1 = 55 q2 = 75 q3 = 90 1 2 3 4 5 Capital per year D E A B C 169。 2020 Pearson Education, Inc. Chapter 6 46 Production: Two Variable Inputs Substituting Among Inputs Companies must decide what bination of inputs to use to produce a certain quantity of output There is a tradeoff between inputs, allowing them to use more of one input and less of another for the same level of output 169。 2020 Pearson Education, Inc. Chapter 6 47 Production: Two Variable Inputs Substituting Among Inputs Slope of the isoquant shows how one input can be substituted for the other and keep the level of output the same The negative of the slope is the marginal rate of technical substitution (MRTS)  Amount by which the quantity of one input can be reduced when one extra unit of another input is used, so that output remains constant 169。 2020 Pearson Education, Inc. Chapter 6 48 Production: Two Variable Inputs The marginal rate of technical substitution equals: )( qLKM R T SI n p u tL a b o rinC h a n g eI n p u tC a p i t a linC h a n g eM R T S of l e v e l f i x e d a f o r169。 2020 Pearson Education, Inc. Chapter 6 49 Production: Two Variable Inputs As labor increases to replace capital Labor bees relatively less productive Capital bees relatively more productive Need less capital to keep output constant Isoquant bees flatter 169。 2020 Pearson Education, Inc. Chapter 6 50 Marginal Rate of Technical Substitution Labor per month 1 2 3 4 1 2 3 4 5 5 Capital per year Negative Slope measures MRTS。 MRTS decreases as move down the indifference curve 1 1 1 1 2 1 2/3 1/3 Q1 =55 Q2 =75 Q3 =90 169。 2020 Pearson Education, Inc. Chapter 6 51 MRTS and Isoquants  We assume there is diminishing MRTS Increasing labor in one unit increments from 1 to 5 results in a decreasing MRTS from 1 to 1/2 Productivity of any one input is limited  Diminishing MRTS occurs because of diminishing returns and implies isoquants are convex  There is a relationship between MRTS and marginal products of inputs 169。 2020 Pearson Education, Inc. Chapter 6 52 MRTS and Marginal Products If we increase labor and decrease capital to keep output constant, we can see how much the increase in output is due to the increased labor Amount of labor increased times the marginal productivity of labor ))(( LMP L 169。 2020 Pearson Education, Inc. Chapter 6 53 MRTS and Marginal Products Similarly, the decrease in output from the decrease in capital can be calculated Decrease in output from reduction of capital times the marginal produce of capital ))(( KMP K 169。 2020 Pearson Education, Inc. Chapter 6 54 MRTS and Marginal Products If we are holding output constant, the effect of increasing labor and decreasing capital must be zero Using changes in output from capital and labor we can see 0 K))(( M P L))(( M P KL 169。 2020 Pearson Education, Inc. Chapter 6 55 MRTS and Marginal Products Rearranging equation, we can see the relationship between MRTS and MPs M R T SKLMPLK)()))(LKLKL( M PK))(( M P ( M P0 K))(( M P L))(( M P169。 2020 Pearson Education, Inc. Chapter 6 56 Isoquants: Special Cases  Two extreme cases show the possible range of input substitution in production 1. Perfect substitutes  MRTS is constant at all points on isoquant  Same output can be produced with a lot of capital or a lot of labor or a balanced mix 169。 2020 Pearson Education, Inc. Chapter 6 57 Perfect Substitutes Labor per month Capital per month Q1 Q2 Q3 A B C Same output can be reached with mostly capital or mostly labor (A or C) or with equal amount of both (B) 169。 2020 Pearson Education, Inc. Chapter 6 58 Isoquants: Special Cases 2. Perfect Complements  Fixed proportions production function  There is no substitution available。