西方經濟學課件

Whenyouhavecompletedyourstudyofthischapter,youwillbeabletoCHAPTERCHECKLISTDefineeconomics,distinguishbetweenmicro-economicsandmacroeconomics,andexplainthequestionsofmicroeconomics.1Describetheworkofeconomistsassocialscientists.Explainfivecoreideasthatdefinetheeconomicwayofthinking.Explainwhyeconomicsisworthstudying.2341.1DEFINITIONSANDQUESTIONS

Alleconomicquestionsandproblemsarisebecausehumanwantsexceedtheresourcesavailabletosatisfythem.Scarcity(稀少性)Theconditionthatarisesbecausetheavailableresourcesareinsufficienttosatisfywants.Facedwithscarcity,wemustmakechoices—wemustchooseamongtheavailablealternatives.Thechoiceswemakedependontheincentivesweface.1.1DEFINITIONSANDQUESTIONS

Incentive(動機)Anincentiveisarewardorapenalty—a“carrot”ora“stick”—thatencouragesordiscouragesanaction.EconomicsThesocialsciencethatstudiesthechoicesthatwemakeaswecopewithscarcityandtheincentivesthatinfluenceandreconcileourchoices.Thesubjecthastwobroaddivisions—microeconomicsandmacroeconomics.1.1DEFINITIONSANDQUESTIONS

Microeconomics(個體經濟學)Microeconomics:Thestudyofthechoicesthatindividualsandbusinessesmake,thewaythesechoicesinteract,andtheinfluencethatgovernmentsexertonthesechoices.Macroeconomics(總體經濟學)Macroeconomics:Thestudyoftheaggregate(ortotal)effectsonthenationaleconomyandtheglobaleconomyofthechoicesthatindividuals,businesses,andgovernmentsmake.1.1DEFINITIONSANDQUESTIONS

MicroeconomicQuestionsWhat?Whatgoodsandservicesgetproducedandinwhatquantities?How?Howaregoodsandservicesproduced?ForWhom?Forwhomarethevariousgoodsandservicesproduced?1.1DEFINITIONSANDQUESTIONS

MacroeconomicQuestionsThethreebigissuesthatmacroeconomicstriestounderstandare:Thestandardofliving(國民所得,失業(yè)率等問題)Thecostofliving(通貨膨脹率等問題)Economicfluctuations(經濟波動等問題)—recessionsandexpansions1.1DEFINITIONSANDQUESTIONS

TheStandardofLivingStandardofliving(生活水準-國民所得)Thelevelofconsumptionofgoodsandservicesthatpeopleenjoy,ontheaverage;itismeasuredbyaverageincomeperperson.GoodsandservicesTheobjectsthatpeoplevalueandproducetosatisfyhumanwants.Goodsarephysicalobjects,andservicesareworkdoneforpeople.1.1DEFINITIONSANDQUESTIONS

Formostpeopleachievingahighstandardoflivingmeansfindingagoodjob.Unemployment(失業(yè)率)Thestateofbeingavailableandwillingtoworkbutunabletofindsuitablework.1.1DEFINITIONSANDQUESTIONS

TheCostofLivingCostoflivingThenumberofdollarsittakestobuythegoodsandservicesthatachieveagivenstandardofliving.Inflation(通貨膨脹)Asituationinwhichthecostoflivingisrisingandthevalueofmoneyisshrinking.1.1DEFINITIONSANDQUESTIONS

EconomicFluctuations:RecessionsandExpansionsBusinesscycle(景氣循環(huán))Aperiodicbutirregularup-and-downmovementinproductionandjobs.TheworstrecessioneverwastheGreatDepression.GreatDepression(經濟大蕭條)Aperiodduringthe1930sinwhichtheeconomyexperienceditsworst-everrecession.1.1DEFINITIONSANDQUESTIONS

Figure1.1showsabusinesscycle.Anexpansionendsatapeakandarecessionendsatatrough.1.2ECONOMICS:ASOCIALSCIENCEGoalofeconomistsistodiscoverhowtheeconomicworldworks.Economistsdistinguishbetween:Positivestatements(實是分析):

WhatisNormativestatements(規(guī)範分析):

WhatoughttobeThetaskofeconomicscience:Todiscoverandcatalogpositivestatementsthatareconsistentwithwhatweobserveintheworldandthatenableustounderstandhowtheeconomicworldworks.1.2ECONOMICS:ASOCIALSCIENCEThetaskcanbebrokenintothreesteps:ObservingandmeasuringModelbuilding(模型建立)Testing(檢定)ObservingandMeasuring Itemssuchas:QuantitiesofresourcesWagesandworkhoursPricesandquantitiesofgoodsandservicesTaxesandgovernmentspendingVolumeofinternationaltrade1.2ECONOMICS:ASOCIALSCIENCEModelBuilding

EconomicmodelAdescriptionofsomeaspectoftheeconomicworldthatincludesonlythosefeaturesoftheworldthatareneededforthepurposeathand.1.2ECONOMICS:ASOCIALSCIENCETestingAmodel’spredictionsmightcorrespondtoorconflictwiththedata.EconomictheoryAgeneralizationthatsummarizeswhatweunderstandabouttheeconomicchoicesthatpeoplemakeandtheeconomicperformanceofindustriesandnations.1.2ECONOMICS:ASOCIALSCIENCEUnscramblingCauseandEffectThecentralideathateconomistsusetounscramblecauseandeffectisceterisparibus.CeterisParibus(假設其他條件不變)

Ceterisparibusmeans“otherthingsbeingequal.”Butceterisparibuscanbeaproblemineconomicswhentestingamodel.1.3THEECONOMICWAYOFTHINKINGFivecoreideas:Rationalchoice(理性選擇)Cost(成本)Benefit(收益)Margin(邊際)Incentives(動機)1.3THEECONOMICWAYOFTHINKINGRationalChoiceUsingtheavailableresourcestosatisfymosteffectivelythewantsofthepersonmakingthechoice.Cost:WhatYouMustGiveUpOpportunitycost

(機會成本)Thehighest-valuedalternativeforgone.SunkCost(隱藏成本)Apreviouslyincurredandirreversiblecost.1.3THEECONOMICWAYOFTHINKINGBenefit:GainMeasuredbyWhatYouAreWillingtoGiveUpBenefitThegainorpleasurethatsomethingbrings.OntheMarginMarginAchoicethatismadebycomparingalltherelevantalternativessystematicallyandincrementally.1.3THEECONOMICWAYOFTHINKINGMarginalCost(邊際成本)Thecostofaone-unitincreaseinanactivityMarginalBenefit(邊際收益)Whatyougainwhenyougetonemore

unitofsomething.MakingaRationalChoiceWhenwetakethoseactionsforwhichmarginalbenefitexceedsorequalsmarginalcost.1.3THEECONOMICWAYOFTHINKINGRespondingtoIncentivesInmakingourchoices,werespondtoincentives.Ifthecostofsomethingrises,wetrytofindalesscostlyalternative.Ifthebenefitofsomethingrises,wedomoreofthatthing.Example:moststudentsbelievethatstudyingjustbeforeanexamhasabiggerbenefitthatstudyingalongtimebeforetheexam.Sostudytimeincreasesastheexamgetscloser.1.4WHYECONOMICSISWORTHSTUDYINGTwomainbenefitsfromstudyingeconomicsare:UnderstandingExpandedcareeropportunitiesUnderstandingEconomicideasareallaroundyou.Youcannotignorethem.Asyouprogresswithyoustudyofeconomics,you’llgainadeeperunderstandingofwhatisgoingonaroundyou.1.4WHYECONOMICSISWORTHSTUDYINGExpandedCareerOpportunitiesMoststudentsofeconomicsdon’tbecomeeconomists.Butknowledgeofeconomicsisvitalinmanyfieldssuchasbanking,finance,business,management,insurance,realestate,law,government,journalism,healthcareandthearts.Economicsgraduatesarenotthehighest-paidprofessional,buttheyareclosetothetop.Graduatesindisciplinesthatteachproblemidentifying,problemsolving,andstrategicbrokeringaretopoftheearningsdistribution:engineeringcomputerscienceeconomicsFigure1.1showssomeearningscomparisons.1.4WHYECONOMICSISWORTHSTUDYINGWhenyouhavecompletedyourstudyofthischapter,youwillbeabletoCHAPTERCHECKLISTDescribewhat,how,andforwhomgoodsandservicesareproducedintheUnitedStates.1Usethecircularflowmodeltoprovideapictureofhowhouseholds,firms,andgovernmentsinteract.Describethemacroeconomicperformance—standardofliving,costofliving,andeconomicfluctuations—oftheUnitedStatesandothereconomies.232.1WHAT,HOW,ANDFORWHOM?

WhatDoWeProduce?Wedividethevastarrayofgoodsandservicesproducedinto:Consumptiongoodsandservices(消費性財貨與勞務)Investmentgoods(資本財)Governmentgoodsandservices(政府部門消費的財貨與勞務)Exportsofgoodsandservices(出口財貨與勞務)ConsumptiongoodsandservicesGoodsandservices

thatareboughtbyindividualsandusedtoprovidepersonalenjoymentandcontributetoaperson’sstandardofliving.Forexample,moviesandLaundromatservices.InvestmentgoodsGoodsthatareboughtbybusinessestoincreasetheirproductiveresources.Forexample,cranesandtrucks.2.1WHAT,HOW,ANDFORWHOM?GovernmentgoodsandservicesGoodsandservices

thatareboughtbygovernments.Forexample,missilesandbridges.ExportsgoodsGoodsandservicesproducedintheUnitedStatesandsoldinothercountries.Forexample,computersandbankingservices.2.1WHAT,HOW,ANDFORWHOM?Figure2.1(a)showstherelativemagnitudesofthedifferenttypesofgoodsandservicesin2002:2.1WHAT,HOW,ANDFORWHOM?Consumption61%Investment13%Government17%Exports9%2.1WHAT,HOW,ANDFORWHOM?Figure2.1(b)showsthelargestfiveitemsofservicesproduced. Andthelargestfiveitemsofgoodsproduced.2.1WHAT,HOW,ANDFORWHOM?HowDoWeProduce?FactorsofproductionTheproductiveresourcesusedtoproducegoodsandservices.Factorsofproductionaregroupedintofourcategories:Land(土地)Labor(勞動)Capital(資本)Entrepreneurship(企業(yè)家精神)2.1WHAT,HOW,ANDFORWHOM?LandLandAllthe“giftsofnature”thatweusetoproducegoodsandservices.Allthethingswecallnaturalresources.Landincludesminerals,water,air,wildplants,animals,birds,andfishaswellasfarmlandandforests.2.1WHAT,HOW,ANDFORWHOM?LaborLaborTheworktimeandworkeffortthatpeopledevotetoproducinggoodsandservices.HumancapitalTheknowledgeandskillthatpeopleobtainfromeducation,on-the-jobtraining,andworkexperience.2.1WHAT,HOW,ANDFORWHOM?Figure2.2showsmeasuresofhumancapitalandhowtheyhavechangedsince1910.2.1WHAT,HOW,ANDFORWHOM?CapitalCapital Tools,instruments,machines,buildings,andotherconstructionsthathavebeenproducedinthepastandthatbusinessesnowusetoproducegoodsandservices.Capitalincludessemifinishedgoods,officebuildings,andcomputers.Capitaldoesnotincludemoney,stocks,andbonds.Theyarefinancialresources.2.1WHAT,HOW,ANDFORWHOM?EntrepreneurshipEntrepreneurshipThehumanresourcethatorganizeslabor,land,andcapital.Entrepreneurs

comeupwithnewideasaboutwhatandhowtoproduce,makebusinessdecisions,andbeartherisksthatarisefromthesedecisions.2.1WHAT,HOW,ANDFORWHOM?ForWhomDoWeProduce?

Factorsofproductionarepaidincomes:

Rent(租金) Incomepaidfortheuseofland. Wages(工資)

Incomepaidfortheservicesoflabor. Interest(利息) Incomepaidfortheuseofcapital.2.1WHAT,HOW,ANDFORWHOM?Profit(orloss)

(投資收益或損失)

Incomeearnedbyanentrepreneurforrunningabusiness.Functionaldistributionofincome

Thepercentagedistributionofincomeamongthefactorsofproduction.Personaldistributionofincome

Thepercentagedistributionofincomeamongindividualpersons.2.1WHAT,HOW,ANDFORWHOM?

Figure2.3(a)showsthefunctionaldistributionofincome: Laborincome72% Netinterestincome8% Personalrentalincome2% Corporateincome9% Proprietors’income9%2.1WHAT,HOW,ANDFORWHOM? Figure2.2(b)showsthepersonaldistributionofincome: Therichest20%earned47%oftotalincome. Thepoorest20%earnedonly5%oftotalincome.2.2CIRCULARFLOWSCircularflowmodelAmodeloftheeconomythatshows:Thecircularflowofexpendituresandincomesthatresultfromdecisionmakers’choicesandthewaythosechoicesinteractinmarketstodeterminewhat,how,andforwhomgoodsandservicesareproduced.2.2CIRCULARFLOWSHouseholdsandFirmsHouseholdsIndividualsorpeoplelivingtogetherasdecision-makingunits.FirmsInstitutionsthatorganizeproductionofgoodsandservices.2.2CIRCULARFLOWSMarketsAmarketisanyarrangementthatbringsbuyersandsellerstogetherandenablesthemtogetinformationanddobusinesswitheachother.Factormarkets

aremarketsinwhichfactorsofproductionareboughtandsold.Goodsmarkets

aremarketsinwhichgoodsandservicesareboughtandsold.2.2CIRCULARFLOWSInfactormarkets:HouseholdssupplyfactorsofproductionFirmshirefactorsofproduction.Firmssupplygoodsandservicesproduced.Householdsbuygoodsandservices.Ingoodsmarkets:RealFlowsandMoneyFlows2.2CIRCULARFLOWSThesearetherealflowsintheeconomyRealFlowsandMoneyFlowsMoneyflowsrunintheoppositedirectiontotherealflows.2.2CIRCULARFLOWSFirmspayhouseholdsincomesfortheservicesoffactorsofproduction.RealFlowsandMoneyFlowsHouseholdspayfirmsforthegoodsandservicestheybuy.Thesearethemoneyflows.Theblueflowsareincomes.Theredflowsareexpenditures.GovernmentsWedividegovernmentsintotwobroadlevels:FederalgovernmentStateandlocalgovernmentFederalGovernmentThefederalgovernment’smajorexpendituresaretoprovide:GoodsandservicesSocialsecurityandwelfarebenefitsTransferstostateandlocalgovernments2.2CIRCULARFLOWSThefederalgovernmentfinancesitsexpendituresbycollectingtaxes.Themaintaxesare:PersonalincometaxesCorporate(business)taxesSocialsecuritytaxesDuringtheearly2000s,thefederalgovernmentisspendingandcollectingintaxesmorethan$2trillionayear—about20centsineverydollarearned.2.2CIRCULARFLOWSStateandLocalGovernmentsStateandlocalgovernmentsexpendituresprovide:GoodsandservicesWelfarebenefitsStateandlocalgovernmentsfinancetheseexpendituresbycollectingtaxes.Themaintaxesleviedare:SalestaxesPropertytaxesStateincometaxes2.2CIRCULARFLOWSHouseholdsandfirmspaytaxesandreceivetransfers. Governmentsbuygoodsandservicesfromfirms.GovernmentintheCircularFlow2.4CIRCULARFLOWSFederalGovernmentExpenditures Figure2.6(a)showsfederalgovernmentexpenditures.2.2CIRCULARFLOWSFederalGovernmentRevenue Figure2.6(b)showsfederalgovernmentrevenue.2.2CIRCULARFLOWSFederalGovernmentExpendituresandRevenueNationaldebtThetotalamountthatthegovernmenthasborrowedtomakeexpendituresthatexceedtaxrevenue—torunagovernmentbudgetdeficit.Duringtheearly2000s,thefederalgovernment’sbudgetisindeficitandthenationaldebtisincreasing.2.2CIRCULARFLOWSStateandLocalGovernmentExpendituresandRevenue

Thelargestpartofthestateandlocalgovernmentsexpendituresareon:EducationHighwaysPublicwelfarebenefits2.2CIRCULARFLOWSStateandLocalGovernmentExpendituresFigure2.7(a)showsstateandlocalgovernmentexpenditures.2.2CIRCULARFLOWSStateandLocalGovernmentRevenueFigure2.7(b)showsstateandlocalgovernmentrevenue.2.2CIRCULARFLOWSStandardofLiving

Standardoflivingdependson:QuantitiesofgoodsandservicesproducedNumberofpeoplewhosharethosegoodsandservicesThegreaterthevalueofproductionperperson,thehigheristhestandardofliving.2.3MACROECONOMICPERFORMANCE

WorldPopulationU.S.population:287,991,639(September8,2002)Worldpopulation:6,248,847,5002.3MACROECONOMICPERFORMANCEClassificationofCountriesAdvancedEconomiesThehighestlivingstandards,28countriesDevelopingEconomiesNotyetachievedahighstandardofliving,128countriesTransitionEconomiesTransitionfromstate-ownershipofcapitaltofreeenterprise,28countries.2.3MACROECONOMICPERFORMANCEFigure2.8showsthestandardoflivingaroundtheworld.Averageincomeperpersonrangesfrom$100adayintheUnitedStatesto$5adayinAfrica.2.3MACROECONOMICPERFORMANCE UnemploymentandLivingStandards

Unemploymentinfluencesthestandardofliving.Theharderitistofindajob,thelongeristheperiodofunemployment.TheaverageunemploymentrateintheUnitedStatesinthepast20yearshasbeen6percentandittakesabout15weekstofindasuitablejob.2.3MACROECONOMICPERFORMANCEFigure2.9showsaverageunemploymentratesaroundtheworld.TheunemploymentrateismuchhigherinSpainthaninmostadvancedeconomies.TheU.S.unemploy-mentrateisamongthelowest.2.3MACROECONOMICPERFORMANCE2.3MACROECONOMICPERFORMANCE2.3MACROECONOMICPERFORMANCECostofLivingTheamountofmoneyittakerstobuythegoodsandservicesthatatypicalfamilyconsumes.InflationTherisingcostofliving.Mostcountriesexperienceinflation,butitsratevariesenormously.Figure2.10showsinflationratesaroundtheworld.TransitioneconomiesandCentralandSouthAmericahavehighaverageinflationrates.2.3MACROECONOMICPERFORMANCEFigure2.10showsinflationratesaroundtheworld.Theleastsevereinflationisin:JapanUnitedStates2.3MACROECONOMICPERFORMANCEEconomicFluctuations

Economiesexpandatanunevenpaceandsometimesshrinkforawhile. Theseebbsandflowarethebusinesscycle.

2.3MACROECONOMICPERFORMANCE2.3MACROECONOMICPERFORMANCEThemostrecentU.S.recessionsoccurredin1991and2001.Betweentheserecessions,theU.S.economyexpandedrapidly. 2.3MACROECONOMICPERFORMANCEThetransitioneconomiesslumpedduringthe1990s.Japanstagnated.ArecessionoccurredinAsiain1998.Whenyouhavecompletedyourstudyofthischapter,youwillbeabletoCHAPTERCHECKLISTDistinguishbetweenquantitydemandedanddemandandexplainwhatdeterminesdemand.1Distinguishbetweenquantitysuppliedandsupplyandexplainwhatdeterminessupply.Explainhowdemandandsupplydeterminepriceandquantityinamarketandexplaintheeffectsofchangesindemandandsupply.23COMPETITIVEMARKETSAmarketisanyarrangementthatbringbuyersandsellerstogether.Inthischapter,westudyacompetitivemarket(完全競爭市場)thathassomanybuyersandsomanysellersthatnoindividualbuyerorsellercaninfluencetheprice.4.1DEMANDQuantitydemanded(需求數(shù)量)Theamountofagood,service,orresourcethatpeoplearewillingandabletobuyduringaspecifiedperiodataspecifiedprice.Thequantitydemandedisanamountperunitoftime.Forexample,theamountperdayorpermonth.4.1DEMANDTheLawofDemand(需求法則)Otherthingsremainingthesame,Ifthepriceofagoodrises,thequantitydemandedofthatgooddecreases.Ifthepriceofagoodfalls,thequantitydemandedofthatgoodincreases.4.1DEMANDDemandScheduleandDemandCurveDemand(需求)Therelationshipbetweenthequantitydemandedandthepriceofagoodwhenallotherinfluencesonbuyingplansremainthesame.

Demandisalistofquantitiesatdifferentpricesandisillustratedbythedemandcurve.4.1DEMANDDemandschedule(需求表)Alistofthequantitiesdemandedateachdifferentpricewhenalltheotherinfluencesonbuyingplansremainthesame.

Demandcurve(需求曲線)Agraphoftherelationshipbetweenthequantitydemandedofagoodanditspricewhenallotherinfluencesonbuyingplansremainthesame.4.1DEMAND4.1DEMANDIndividualDemandandMarketDemandMarketdemand

(市場需求)Thesumofthedemandsofallthebuyersinamarket.Themarketdemandcurveisthehorizontalsum(水平加總)ofthedemandcurvesofallbuyersinthemarket.4.1DEMAND4.1DEMANDChangesinDemand

Changeinthequantitydemanded(需求量變動)Achangeinthequantityofagoodthatpeopleplantobuythatresultsfromachangeinthepriceofthegood.Changeindemand(需求變動)Achangeinthequantitythatpeopleplantobuywhenanyinfluenceotherthanthepriceofthegoodchanges.(除了價格以外的其他變數(shù)改變)4.1DEMANDFigure4.3showschangesindemand.1. Whendemanddecreases,thedemandcurveshiftsleftwardfromD0toD1.2. Whendemandincreases,thedemandcurveshiftsrightwardfromD0toD2.4.1DEMAND

Themaininfluencesonbuyingplansthatchangedemandare:Pricesofrelatedgoods(其他相關財貨價格)Income(所得)Expectations(預期)NumberofbuyersPreferences(偏好)4.1DEMANDPricesofRelatedGoodsSubstitute(替代品)Agoodthatcanbeconsumedinplaceofanothergood.Forexample,applesandoranges.Thedemandforagoodincreases,ifthepriceofoneofitssubstitutesrises.Thedemandforagooddecreases,ifthepriceofoneofitssubstitutesfalls.4.1DEMANDComplement(互補品)Agoodthatisconsumedwithanothergood.Forexample,icecreamandfudgesauce.Thedemandforagoodincreases,ifthepriceofoneofitscomplementsfalls.Thedemandforagooddecreases,ifthepriceofoneofitscomplementsrises.4.1DEMANDIncome Thedemandforanormalgood(正常財)increases

ifincome increases. Thedemandforaninferiorgood(劣等財)decreases

ifincomeincreases.4.1DEMANDExpectationsExpectedfutureincomeandexpectedfuturepricesinfluencedemandtoday.Forexample,ifthepriceofacomputerisexpectedtofallnextmonth,thedemandforcomputerstodaydecreases.NumberofBuyersThegreaterthenumberofbuyersinamarket,thelargeristhedemandforanygood.

4.1DEMAND PreferencesWhenpreferences

change,thedemandforoneitemincreasesandthedemandforanotheritem(oritems)decreases.Preferenceschangewhen:PeoplebecomebetterinformedNewgoodsbecomeavailable.4.1DEMANDDemand:ASummary4.2SUPPLYQuantitysupplied(供給數(shù)量)Theamountofagood,service,orresourcethatpeoplearewillingandabletosellduringaspecifiedperiodataspecifiedprice.TheLawofSupply(供給法則)Otherthingsremainingthesame,Ifthepriceofagoodrises,thequantitysupplied ofthatgoodincreases.Ifthepriceofagoodfalls,thequantitysuppliedof thatgooddecreases.4.2SUPPLYSupplySchedule(供給表)andSupplyCurve(供給曲線)Supply(供給)Therelationshipbetweenthequantitysuppliedofagoodandthepriceofthegoodwhenallotherinfluencesonsellingplansremainthesame.Supplyalistofquantitiesatdifferentpricesandisillustratedbythesupplycurve.4.2SUPPLYSupplyscheduleAlistofthequantitiessuppliedateachdifferentprice whenallotherinfluencesonsellingplansremain thesame.Supplycurve

Agraphoftherelationshipbetweenthequantity suppliedandthepriceofthegoodwhenallotherinfluenceson sellingplansremainthesame.4.2SUPPLY4.2SUPPLYIndividualSupplyandMarketSupplyMarketsupply(市場供給)Thesumofthesuppliesofallsellersinamarket.Themarketsupplycurveisthehorizontalsumofthesupplycurvesofallthesellersinthemarket.4.2SUPPLY4.2SUPPLYChangesinSupplyChangeinquantitysupplied(供給數(shù)量變動)Achangeinthequantityofagoodthatsuppliersplantosellthatresultsfromachangeinthepriceofthegood.Changeinsupply(供給變動)Achangeinthequantitythatsuppliersplantosellwhenanyinfluenceonsellingplansotherthanthepriceofthegoodchanges.4.2SUPPLY2. Whensupplyincreases,thesupplycurveshiftsrightwardfromS0toS2.1. Whensupplydecreases,thesupplycurveshiftsleftwardfromS0toS1.Figure4.7showschangesinsupply.4.2SUPPLY4.2SUPPLYThemaininfluencesonsellingplansthatchangesupplyare:PricesofrelatedgoodsPricesofresourcesandotherInputs(投入要素價格)ExpectationsNumberofsellersProductivity4.2SUPPLYPricesofRelatedGoodsAchangeinthepriceofonegoodcanbringachangeinthesupplyofanothergood.SubstituteinproductionAgoodthatcanbeproducedinplaceofanothergood.Forexample,atruckandanSUVinanautofactory.Thesupplyofagoodincreasesifthepriceofoneofitssubstitutesinproductionfalls.Thesupplyagooddecreasesifthepriceofoneofitssubstitutesinproductionrises.4.2SUPPLYComplementinproductionAgoodthatisproducedalongwithanothergood.Forexample,strawisacomplementinproductionofwheat.Thesupplyofagoodincreasesifthepriceofoneofitscomplementsinproductionrises.Thesupplyagooddecreasesifthepriceofoneofitscomplementsinproductionfalls.4.2SUPPLYPricesofResourcesandOtherInputs Resourceandinputpricesinfluencethecostofproduction.Andthemoreitcoststoproduceagood,thesmalleristhequantitysuppliedofthatgood.ExpectationsExpectationsaboutfuturepricesinfluencesupply.Expectationsoffutureinputpricesalsoinfluencesupply.4.2SUPPLYNumberofSellers Thegreaterthenumberofsellersinamarket,thelargerissupply.

Productivity(生產力) Productivityisoutputperunitofinput. Anincreaseinproductivitylowerscostsandincreasessupply.4.2SUPPLYSupply:ASummary4.3MARKETEQUILIBRIUMMarketequilibrium(市場均衡) Whenthequantitydemandedequalsthequantitysupplied—whenbuyers’andsellers’plansareconsistent.Equilibriumprice(均衡價格) Thepriceatwhichthequantitydemandedequalsthequantitysupplied.Equilibriumquantity(均衡數(shù)量) Thequantityboughtandsoldattheequilibriumprice.4.3MARKETEQUILIBRIUMFigure4.9showstheequilibriumpriceandequilibriumquantity.1.Marketequilibriumatthe intersectionofthedemandcurveandthesupplycurve.2.Theequilibriumpriceis$1abottle.3.Theequilibriumquantityis10millionbottlesaday.4.3MARKETEQUILIBRIUMPrice:AMarket’sAutomaticRegulatorLawofmarketforces(市場機能)Whenthereisashortage,thepricerises.Whenthereisasurplus,thepricefalls.Surplus

or

ExcessSupply(超額供給)Thequantitysuppliedexceedsthequantitydemanded.Shortage

or

ExcessDemand(超額需求)Thequantitydemandedexceedsthequantitysupplied.4.3MARKETEQUILIBRIUMFigure4.10(a)marketachievesequilibrium.At$1.50abottle:1.Quantitysuppliedis11bottles.3.Thereisasurplus.4.Pricefallsuntilthemarketisinequilibrium.2.Quantitydemandedis9bottles.4.3MARKETEQUILIBRIUMFigure4.10(b)marketachievesequilibrium.At75centsabottle:5.Quantitydemandedis11bottles.7.Thereisashortage.8.Pricerisesuntilthemarketisinequilibrium.6.Quantitysuppliedis9bottles.4.3MARKETEQUILIBRIUMFigure4.11(a)showstheeffectsofanincreaseindemand.1.Anincreaseindemandshiftsthedemandcurverightward.2.Thepricerisestorestoremarketequilibrium.3.Quantitysuppliedincreasesalongthesupplycurve.4.Equilibriumquantityincreases.4.3MARKETEQUILIBRIUMFigure4.11(b)showstheeffectsofadecreaseindemand.1.Adecreaseindemandshiftsthedemandcurveleftward.2.Thepricefallstorestoremarketequilibrium.3.Quantitysupplieddecreasesalongthesupplycurve.4.Equilibriumquantitydecreases.4.3MARKETEQUILIBRIUMEffectsofChangesinDemand(需求變動影響)Whendemandchanges:Thesupplycurvedoesnotshif