克鲁格曼国际经济学答案解析

WORD格式-可编辑专业知识--整理分享Chapter31.In1986,thepriceofoilonworldmarketsdroppedsharply.SincetheUnitedStatesisanoil-importingcountry,thiswaswidelyregardedasgoodfortheU.S.economy.YetinTexasandLouisiana1986wasayearofeconomicdecline.Why?ItcandeducethatTexasandLouisianaareoil-producingstatesofUnitedStates.Sowhenthepriceofoilonworldmarketsdeclined,therealwageofthisindustryfellintermsofothergoods.Thismightbethereasonofeconomicdeclineinthesetwostatesin1986.2。Aneconomycanproducegood1usinglaborandcapitalandgood2usinglaborandland.Thetotalsupplyoflaboris100units.Giventhesupplyofcapital,theoutputsofthetwogoodsdependsonlaborinputasfollows:Toanalyzetheeconomy’sproductionpossibilityfrontier,considerhowtheoutputmixchangesaslaborisshiftedbetweenthetwosectors.a.Graphtheproductionfunctionsforgood1andgood2.),(),(22221111LKQQLKQQProductionFunctionforGood1025.138.148.657.56673.680.787.493.910001020304050607080901000102030405060708090100LaborInputforGood1OutputProductionFunctionforGood2039.852.561.869.375.881.586.791.495.510001020304050607080901000102030405060708090100LaborInputforGood2OutputWORD格式-可编辑专业知识--整理分享b.Graphtheproductionpossibilityfrontier.Whyisitcurved?ThePPFiscurvedduetodecliningmarginalproductoflaborineachgood.Thetotallaborsupplyisfixed.SoasL1rises,MPL1falls;correspondingly,asL2falls,MPL2rises.SoPPgetssteeperaswemovedownittotheright.2.Themarginalproductoflaborcurvescorrespondingtotheproductionfunctionsinproblem2areasfollows:a.Supposethatthepriceofgood2relativetothatofgood1is2.Determinegraphicallythewagerateandtheallocationoflaborbetweenthetwosectors.Withtheassumptionthatlaborisfreelymobilebetweensectors,itwillmovefromthelow-wagesectortothehigh-wagesectoruntilwagesareequalized.Soinequilibrium,thewagerateisequaltothevalueoflabor’smarginalproduct.2/122211PPPMPLPMPLQ1Q2L1L2PPF),(2222LKQQ),(1111LKQQ100100WORD格式-可编辑专业知识--整理分享Theabscissaofpointofintersectionillustratedaboveshouldbebetween(20,30).Sinceweonlyhavetofindouttheapproximateanswer,linearfunctioncouldbeemployed.ThelaborallocationbetweenthesectorsisapproximatelyL1=27andL2=73.Thewagerateisapproximately0.98.b.Usingthegraphdrawnforproblem2,determinetheoutputofeachsector.Thenconfirmgraphicallythattheslopoftheproductionpossibilityfrontieratthatpointequalstherelativeprice.TherelativepriceisP2/P1=2andwehavegottheapproximatelaborallocation,sowecanemploythelinearfunctionagaintocalculatetheapproximateoutputofeachsector:Q1=44andQ2=90.c.Supposethattherelativepriceofgood2fallsto1.Repeat(a)and(b).Q1Q2L1L2PPF),(2222LKQQ),(1111LKQQ10010021slopeWORD格式-可编辑专业知识--整理分享Therelativedeclineinthepriceofgood2causedlabortobereallocated:laborisdrawnoutofproductionofgood2andentersproductionofgood1(Ｌ1=62,L2=38).Thisalsoleadstoanoutputadjustment,thatis,productionofgood2fallsto68unitsandproductionofgood1risesto76units.Andthewagerateisapproximatelyequalto0.74.d.Calculatetheeffectsofthepricechangeontheincomeofthespecificfactorsinsectors1and2.WiththerelativepricechangefromP2/P1=2toP2/P1=1,thepriceofgood2hasfallenby50percent,whilethepriceofgood1hasstayedthesame.Wageshavefallentoo,butbylessthanthefallinP2(wagesfellapproximately25percent).Thus,therealwagerelativetoP2actuallyriseswhilerealwagerelativetoP1falls.Hence,todeterminethewelfareconsequenceforworkers,theinformationabouttheirconsumptionsharesofgood1andgood2isneeded.Q1Q2L1L2PPF),(2222LKQQ),(1111LKQQ1001001slope21slopeWORD格式-可编辑专业知识--整理分享3.Inthetextweexaminedtheimpactsofincreasesinthesupplyofcapitalandland.Butwhatifthemobilefactor,labor,increasesinsupply?a．Analyzethequalitativeeffectsofanincreaseinthesupplyoflaborinthespecificfactorsmodel,holdingthepriceofbothgoodsconstant.Foraneconomyproducingtwogoods,XanY,withlabordemandsreflectedbytheirmarginalrevenueproductcurves,thereisaninitialwageofw1andaninitiallaborallocationofLx=OxAandLy=OyA.Whenthesupplyoflaborincreases,therightboundaryofthediagramillustratedbelowpushedouttoOy’.ThedemandforlaborinsectorYispulledrightwardwiththeboundary.Thenewintersectionofthelabordemandcurvesshowsthatlaborexpandsinbothsectors,andthereforeoutputofbothXandYalsoexpand.Therelativeexpansionofoutputisambiguous.Wagespaidtoworkersfall.b．Graphtheeffectontheequilibriumforthenumericalexampleinproblems2and3,givenarelativepriceof1,whenthelaborforceexpandsfrom100to140.Withthelawofdiminishingreturns,thenewproductionpossibilityfrontierismoreconcaveandsteeper(flatter)attheendswhentotallaborsupplyincreases.L1increaseto90from62andL2increasesto50from38.Wagesdeclinefrom0.74to0.60.ThisnewallocationoflaborleadstoanewoutputmixofapproximatelyQ1=85andQ2=77.WxxPMPLyyPMPL1w2wyOyOABWORD格式-可编辑专业知识--整理分享Chapter41．IntheUnitedStateswherelandischeap,theratiooflandtolaborusedincattlerisingishigherthanthatoflandusedinwheatgrowing.Butinmorecrowdedcountries,wherelandisexpensiveandlaborischeap,itiscommontoraisecowsbyusinglesslandandmorelaborthanAmericansusetogrowwheat.Canwestillsaythatraisingcattleislandintensivecomparedwithfarmingwheat?Whyorwhynot?Thedefinitionofcattlegrowingaslandintensivedependsontheratiooflandtolaborusedinproduction,notontherati