Chapter2TheLawofComparativeAdvantage2.1IntroductionThebasicquestionsthatweseektoanswerinthischapterare:Whatisthebasisfortradeandwhatarethegainsfromtrade?Whatisthepatteroftrade?2.2TheMercantilists’viewsontradeMercantilistsmaintainedthatthewayforanationtobecomerichandpowerfulwastoexportmorethanitimported.Andtheypreachedeconomicnationalism,believingthatonenationcouldgainonlyattheexpenseofothernations.Sonationalinterestswerebasicallyinconflict.Question1Whydidmercantilists’viewoninternationaltradecouldbeadoptedbyrulersatthattime?Task1ReadthecasestudyquotedfromThomasMunnTask2FindingoutthereasonsforustounderstandMercantilistsviewontradefirstonpage32.Question2Studythecasestudy2-2andfindoutevidencetoprovetheresurgenceofneomercantilismintoday’sworldtrade.

2.3

TradeBasedonAbsoluteAdvantage:AdamSmith2.3AAbsoluteAdvantage當(dāng)一國(guó)相對(duì)于另一國(guó)在某種商品的生產(chǎn)上有更高的效率（或絕對(duì)優(yōu)勢(shì)），但在另一種商品生產(chǎn)上效率較低（或有絕對(duì)劣勢(shì)），那么兩國(guó)就可以通過(guò)專(zhuān)門(mén)生產(chǎn)自己有絕對(duì)優(yōu)勢(shì)的產(chǎn)品，并用其中的一部分來(lái)交換其有絕對(duì)劣勢(shì)的商品。這樣資源就可以最有效地被利用，而且兩種商品的產(chǎn)出會(huì)有很大的增長(zhǎng)。AdamSmithstronglyadvocatedapolicyoflaissez-faireashebelievedthatfreetradewouldcauseworldresourcestobeutilizedmoreefficientlyandwouldmaximizeworldwelfare.2.4TradeBasedonComparativeAdvantage:DavidRicardo2.4ATheLawofComparativeAdvantageAccordingtothelawofcomparativeadvantage,evenifonenationislessefficientthan(hasanabsolutedisadvantagewithrespectto)theothernationintheproductionofbothcommodities,thereisstillabasisformutuallybeneficialtrade.Thefirstnationshouldspecializeintheproductionofandexportthecommodityinwhichitsabsolutedisadvantageissmaller(thisisthecommodityofitscomparativeadvantage)andimportthecommodityinwhichitsabsolutedisadvantageisgreater(thisisthecommodityofitscomparativedisadvantage)

比較優(yōu)勢(shì)原理：即使一國(guó)在兩種商品的生產(chǎn)上較之另一國(guó)均出處于絕對(duì)劣勢(shì)（即無(wú)絕對(duì)優(yōu)勢(shì)），仍有可能進(jìn)行互利貿(mào)易。一個(gè)國(guó)家可以專(zhuān)門(mén)生產(chǎn)出口其絕對(duì)劣勢(shì)較小的商品（這是其具有比較優(yōu)勢(shì)的商品）同時(shí)進(jìn)口其絕對(duì)劣勢(shì)相對(duì)較大的商品（這是其具有比較劣勢(shì)的商品）CommoditiesU.SU.K（產(chǎn)品）Wheat（bushels/man-hour)小麥（蒲式耳/勞動(dòng)小時(shí)）61Cloth(yards/man-hour)布（碼/勞動(dòng)小時(shí)）42Thespreadbetween12Cand4C(I.e.,8C)representsthetotalgainsfromtradeavailabletobesharedbythetwonationsbytrading6W.Theclosertherateofexchangeisto4C=6W,thesmalleristheshareofgaingoingtotheUnitedStates.Theclosertherateofexchangeisto6W=12C,thegreateristhegainoftheUnitedStatesrelativetothatoftheUnitedKingdom.Question3iftherateofexchangeis6W=10C,howshouldgainsbesharedbyU.S.andU.K.?2.4CExceptiontotheLawofComparativeAdvantageThisoccurswhentheabsolutedisadvantagethatonenationhaswithrespecttoanothernationisthesameforbothcommodities.CommoditiesU.SU.K（產(chǎn)品）Wheat（bushels/man-hour)小麥（蒲式耳/勞動(dòng)小時(shí)）63Cloth(yards/man-hour)布（碼/勞動(dòng)小時(shí)）42DollarPriceofWheatandClothintheU.S.andU.K.ThisisalwaysthecaseaslongastheU.K.wagerateisbetween1/6and?oftheU.S.wagerate(thesameastheproductivitydifferencebetweentheU.K.andtheU.S.intheproductionofwheatandcloth.CommoditiesU.SU.K（產(chǎn)品）PriceofOnebushelofWheat一蒲式耳小麥的價(jià)格$1$2PriceofoneyardofCloth一碼布的價(jià)格$1.5$1Iftheexchangeratebetweenthedollarandthepoundwere￡1=$1,sothattheU.K.wageratewasexactly1/6theU.S.wagerate.TradewouldbeunbalancedinfavoroftheU.K.andtheexchangeratebetweenthedollarandthepoundwouldhavetorise.CommoditiesU.SU.K（產(chǎn)品）PriceofOnebushelofWheat一蒲式耳小麥的價(jià)格$1$1PriceofoneyardofCloth一碼布的價(jià)格$1.5$0.5Taskafterclass,readcase-study2-3andseehowthewriterisagainsttheideaofprotectinghighwagesandstandardoflivingbytraderestrictions.2.5ComparativeAdvantageandOpportunityCost（比較優(yōu)勢(shì)與機(jī)會(huì)成本）Ricardobasedhislawofcomparativeadvantageonanumberofsimplifyingassumptions:(1)twonationsandtwocommodities(2)freetrade(3)perfectmobilityoflaborwithineachnationbutimmobilitybetweentwonations,(4)constantcostofproduction(5)notransportationcosts,(6)notechnicalchange,(7)thelabortheoryofvalue.2.5AComparativeAdvantageandtheLaborTheoryofValueUndertheLabortheoryofvalue,thevalueorthepriceofacommoditydependsexclusivelyontheamountoflaborgoingintotheproductionofthecommodity.Theeitherlaboristheonlyfactorofproductionortheproductionoflaborisusedinthesamefixedproportionintheproductionofallcommodities.Laborishomogeneous(ofonlyonetype)2.5BTheOpportunityCostTheory(機(jī)會(huì)成本理論）CommoditiesU.SU.K（產(chǎn)品）Wheat（bushels/man-hour)小麥（蒲式耳/勞動(dòng)小時(shí)）61Cloth(yards/man-hour)布（碼/勞動(dòng)小時(shí)）42CommoditiesU.SU.K（產(chǎn)品）（OpportunityCostfor)Wheat小麥（機(jī)會(huì)成本）2/3C2C(OpportunityCostfor)Cloth布（機(jī)會(huì)成本）3/2W1/2WThenationwithloweropportunitycostintheproductionofacommodityhasacomparativeadvantageinthatcommodity.2.5CTheProductionPossibilityFrontierunderConstantCost(固定成本下的生產(chǎn)可能性曲線(xiàn)）Productionpossibilityfrontierortransformationcurveisacurvethatshowsthealternativecombinationoftwocommoditiesthatanationcanproducebyfullyutilizingallofitsresourceswiththebesttechnologyavailabletoit.生產(chǎn)可能性曲線(xiàn)也叫轉(zhuǎn)換曲線(xiàn)是指一國(guó)使用其所有資源和最佳技術(shù)所能生產(chǎn)的兩種商品的各種組合。LookingatTable2.4andtheSchedulesaregraphedasproductionpossibilityfrontiersinFigure2.1U.S.180AB90600Cloth120Wheat180B’U.K.60012040

40ClothWheatA’Eachpointonafrontierrepresentsonecombinationofwheatandcloththatthenationcanproduce.Thefrontiersaredownward,ornegativelysloped.Straight-lineproductionpossibilityfrontiersreflectconstantopportunitycost.Pointsinsideorbelow,theproductionpossibilityfrontierarealsopossiblebutareinefficient.Pointsabovetheproductionfrontiercannotbeachievedwiththeresourcesandtechnologycurrentlyavailabletothenation.Undertheassumptionsthatpricesequalcostsofproductionandthatthenationdoesproducebothsomewheatandsomecloth,theopportunitycostofwheatisequaltothepriceofwheatrelativetothepriceofcloth(Pw/Pc).Thedifferenceinrelativecommoditypricesbetweenthetwonationsisareflectionofthe