《劳动经济学》(作者Borjas)第四章习题答案.pdf

《《劳动经济学》(作者Borjas)第四章习题答案.pdf》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、CHAPTER44-1.Supposetherearetwoinputsintheproductionfunction,laborandcapital,andthesetwoinputsareperfectsubstitutes.Theexistingtechnologypermits1machinetodotheworkof3persons.Thefirmwantstoproduce100unitsofoutput.Supposethepriceofcapitalis$750permachineperweek.

2、Whatcombinationofinputswillthefirmuseiftheweeklysalaryofeachworkeris$300?Whatcombinationofinputswillthefirmuseiftheweeklysalaryofeachworkeris$225?Whatistheelasticityoflabordemandasthewagefallsfrom$300to$225?Becauselaborandcapitalareperfectsubstitutes,theisoqu

3、ants(inbold)arelinearandthefirmwilluseonlylabororonlycapital,dependingonwhichischeaperinproducing100unitsofoutput.The(absolutevalueofthe)slopeoftheisoquant(MPE/MPK)is1/3because1machinedoestheworkof3men.Whenthewageis$900(leftpanel),theslopeoftheisocostis300/75

4、0.Theisocostcurve,therefore,issteeperthantheisoquant,andthefirmonlyhirescapital(atpointA).Whentheweeklywageis$225(rightpanel),theisoquantissteeperthantheisocostandthefirmhiresonlylabor(atpointB).WeeklySalary=$300WeeklySalary=$225CapitalCapitalAslope=MPE/MPKsl

5、ope=MPE/MPK=1/3=1/3slope=w/rslope=w/r=300/750=225/750BLaborLaborTheelasticityoflabordemandisdefinedasthepercentagechangeinlabordividedbythepercentagechangeinthewage.Becausethedemandforlaborgoesfrom0toapositivequantitywhenthewagedroppedto$225,the(absolutevalue

6、ofthe)elasticityoflabordemandisinfinity.224-2.(a)Whathappenstothelong-rundemandcurveforlaborifthedemandforthefirm’soutputincreases?ThelabordemandcurveisgivenbyVMPE=MRxMPE.Asdemandforthefirm’soutputincreases,itsmarginalrevenuealsoincreases.Thus,anincreaseindem

7、andforthefirm’soutputshiftsthelabordemandcurvetotheright.(b)Whathappenstothelong-rundemandcurveforlaborifthepriceofcapitalincreases?Todeterminehowanincreaseinthepriceofcapitalchangesthedemandforlabor,supposeinitiallythatthefirmisproducing200unitsofoutputatpoi

8、ntPinthefigure.Theincreaseinthepriceofcapital(assumingcapitalisanormalinput)increasesthemarginalcostsofthefirmandwillreducetheprofit-maximizinglevelofoutputtosay100units.Theincreaseinthep