生产函数决定成本函数(英文版)

Production and Costs in the Short Run
• Limited options in short run (SR) • Initial assumption
– Firm can hire more labor
Production in the Short Run
• Total product (TP) of labor
EXHIBIT 6.2 The Stages of Production
Variable Costs in the SR
• Constructing the firm’s variable cost curve
– Need total product curve – Need wage rate
Chapter 6 Production and Costs
Steven Landsburg, University of Rochester
Copyright ©2005 by Thomson South-Western, part of the Thomson Corporation. All rights reserved.
Exhibit 6.3 VC Curve
N
TP
Q
VC
TC
1
5
5
15
65
2
12
12
30
80
3
21
21
45
95
4
28
28
60
110
5ቤተ መጻሕፍቲ ባይዱ
33
33
75
125
6
36
36
90
140
7
37
37
105
155
EXHIBIT 6.3 Variable Cost Curve
Fixed Costs in the SR
• Costs of capital
• 產量受到生產技術與生產要素的影響 • Where do cost curves come from • Depends on firm’s available technology • Determines production process • Production process determines firm’s costs
• Additional cost considerations beside totals
Computing Average and Marginal Costs
• Average variable cost (AVC): variable cost divided by quantity of output
L
EXHIBIT 6.1 Total, Marginal and Average Products
Shape of MP and AP Curves
• AP
– If number of workers large, additional workers cause average product of labor to decrease
much output can be produced with a given basket of inputs
Calculating MP and AP
• Marginal product of labor (MPL)
– Increase in total product based on hiring one additional worker
Introduction
• 生產函數決定成本函數，而(邊際)成本會影響供給函數； 因此，本章先介紹生產函數，然後說明成本函數。
• 生產函數在說明生產要素與產量之間的關係；生產要素分 為兩類，一類是短期即可變動其使用的數量的(以勞工為 代表)，另一類是長期才可變動其使用的數量的(以資本為 代表) 。
– Inverted U-shape
• MP
– Inverted U-shape
• AP and MP relationship to one another
– If MP > AP, MP lies above AP – If MP < AP, MP lies below AP – If MP = AP, AP at maximum or peak
短期 TP Q f ( K , L ), APL TP Q ,
LL MPL dTP dQ
dL dL 長期 TP Q f ( K , L )
MPL&APL
MPL dTP , APL TP
dL
L
dAPL
d TP L
L dTP dL
TP
0
dL dL
L2
dTP TP dL L 0 MPL APL
• Price of hiring labor
– Multiply number of workers by wage rate to get variable cost PL×L=VC
– Curve relates total product, not number of workers, to variable cost
– Assume capital fixed – Slope of TP
• Average product of labor (APL)
– Total product divided by number of workers
Relation between MP and AP
TP
N
Calculating MP and AP
– Quantity of output produced by firm in a given amount of time dependent on labor hired
– Information graphically represented by production function
• Production function slopes upward • Production function is rule for determining how
– Physical assets, such as machinery and factories
– Ex. handyman’s van
Total Cost
• Total cost equal to sum of fixed and variable costs of production TC=FC+VC=FC+PL×L