-Tsinghua-Micro-Ch21-Cost-Curves课件_第1页
-Tsinghua-Micro-Ch21-Cost-Curves课件_第2页
-Tsinghua-Micro-Ch21-Cost-Curves课件_第3页
-Tsinghua-Micro-Ch21-Cost-Curves课件_第4页
-Tsinghua-Micro-Ch21-Cost-Curves课件_第5页
已阅读5页,还剩34页未读 继续免费阅读

下载本文档

版权说明:本文档由用户提供并上传,收益归属内容提供方,若内容存在侵权,请进行举报或认领

文档简介

1、Chapter Twenty-OneCost CurvesWhat do we do in this chapter?We examine how c(y) varies with y.Why? We need to prepare ourselves for studying firms supply.We have the following types of cost curves:A total cost curve and average total cost curveA variable cost curve and average variable cost curveAn a

2、verage fixed cost curve Marginal cost curveComparing consumer behavior with producer behavior Consumer: Maximize Utility subject to linear constraint; Producer: Minimize linear function subject to production function; Minimizing a linear function makes things much simpler; Also, the production funct

3、ion is cardinal; utility is ordinal !From last Chapter: Short-Run & Long-Run Total Costsx1x2Short-runoutputexpansionpathLong-run costs are:Short-run costs are:Fixed, Variable & Total Cost Functions Let F be the short-run fixed cost F does not vary with the firms output level. Let cv(y) be the variab

4、le cost function.Then the total cost function isy$Fcv(y)c(y)FAv. Fixed, Av. Variable & Av. Total Cost CurvesFor y 0, the firms average total cost function is$/output unitAFC(y)y0AFC(y) 0 as y Av. Fixed, Av. Variable & Av. Total Cost Curves How about the average variable cost? It must be increasing e

5、ventually Since at least one input is fixed in the short-run.$/output unitAFC(y)AVC(y)ATC(y)y0Since AFC(y) 0 as y ,ATC(y) AVC(y) as y .And since short-run AVC(y) musteventually increase, ATC(y) must eventually increase in a short-run.Marginal Cost FunctionSince the firms total cost function is:The m

6、arginal cost is:Marginal and Variable Cost FunctionsNote:Marginal and Variable Cost FunctionsMC(y)y0Area is the variablecost of making y units$/output unitHow is marginal cost related to average variable cost?SinceTherefore,as$/output unityAVC(y)MC(y)The short-run MC curve intersectsthe short-run AV

7、C curve frombelow at the AVC curves minimum.MC and ATC are similarly relatedSimilarly, sinceTherefore,as$/output unityMC(y)ATC(y)as$/output unityAVC(y)MC(y)ATC(y)Short-Run & Long-Run Total Cost CurvesSuppose the firm can be in one of just three short-runs;x2 = x2 or x2 = x2 x2 x2 x2.or x2 = x2.yF0F

8、= w2x2F = w2x2A larger amount of the fixedinput increases the firmsfixed cost. Why does a larger amount of the fixed input reduce the slope of the firms total cost curve?cs(y;x2)cs(y;x2)$FLet MP1 be the marginal physical productivity of the variable input 1;So the firms extra cost from producing one

9、 extra unit of output is3.This is the slope of the firms total cost curve.4.If input 2 is a complement to input 1 thenMP1 is higher for higher x2. Hence, MC is lower for higher x2.Short-Run & Long-Run Total Cost CurvesShort-Run & Long-Run Total Cost CurvesThe firm has three short-run total cost curv

10、es.In the long-run, how does the firm choose amongst these three?yF0FyyFor 0 y y, choose x2 = x2.cs(y;x2)cs(y;x2)cs(y;x2)$FyF0FyyFor 0 y y, choose x2 = x2.For y y y, choose x2 = x2.cs(y;x2)cs(y;x2)cs(y;x2)$FyF0Fcs(y;x2)yyFor 0 y y, choose x2 = x2.For y y y, choose x2 = x2.For y y, choose x2 = x2.cs(y;x2)cs(y;x2)$FyF0cs(y;x2)cs(y;x2)Fcs(y;x2)yyFor 0 y y, choose x2 = x2.For y y y, choose x2 = x2.For y 0, the long-run MC equals theMC

温馨提示

  • 1. 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
  • 2. 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
  • 3. 本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
  • 4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
  • 5. 人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对用户上传分享的文档内容本身不做任何修改或编辑,并不能对任何下载内容负责。
  • 6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
  • 7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。

评论

0/150

提交评论