曼昆的《微觀經(jīng)濟(jì)學(xué)原理》課業(yè)筆記英文版

Ch1TenPrinciplesofeconomicScarcity:thelimitednatureofsociety'sresourcesEconomics:thestudyofhowsocietymanagesitsscarceresources,e.g.Thereare10principleofeconomicwhichareneededtoberememberthroughout.Peoplefacetrade-off1.Individual(time,money)andsociety(efficiencyvsequality).?Costofsomethingiswhatyourgiveuptogetit.\1.Theopportunitycostofanyitemiswhatevermustbegivenuptoobtainit.?Rationalpeoplethinkingatmargin(effectofoneadditionalitem)1.Thisprincipleassumethateveryoneisrationalpeople(madetheirdecisionbaseontheirinterests)thiswasaddressedonAdamSmith'sWealthofNation.?Peoplerespondtoincentives(誘惑物)Thisstatementrevealsthathumafeatureineconomicstudy.?Tradecanmakeeveryonebetter-off1.Ex:tradeofagriculturalproductandtechnologybetweenJapanandAmerica,itwillbreakthelawofPPF.Itinvolvedabsoluteadvantages(lowinput)andcomparativeadvantage(lowopportunitycostwin)?Marketsareusuallyagoodwaytoorganizeeconomyactivity.Marketscanbalancetheprice.Governmentcansometimeimprovemarketoutcome.Acountry'sstandardoflivingdependsonitsabilitytoproducegoodsandservices.Pricerisewhengovernmentprinttoomuchmoney.SocietyFacesaShort-runTradeoffBetweenInflationandUnemploymentCh2Thinkinglikeaeconomist2018年2月6日16:32Economistsplaytworoles:Scientists:trytoexplaintheworld.Policyadvisors:trytoimproveitBaseonthesetworoles,theyhavetwotypesofstatement.Normativeandpositive.Inmyopinion,economistsasascientiststendtousepositivestatement,becausepositivestatementisbaseonfact,anditistestable.Policyadvisorsusebothpositiveandnormative,becausetheyneedtogiveappropriateadvicetoimproveoverallstandardofliving.Therefore,theywillcomeoutwithsomenormativestatementtoaddresstheiropinion,andusepositivestatementtoprovetheirnormativestatement.Assumptions:becauseoftheworldiscomplex,therearetwomuchvariables,anditsunliketofititinallonemodels.Therefore,economistsneedtomakeasimplifyassumptionswheremostofthetimeonlyhavetwocoordinateswithtwovariables.Ex:CountriesAandcountriesBaretradingproductsXandY.Ch3Interdependenceandthegainsfromtrade2018年2月6日16:28Absoluteadvantage:TheabilitytoproduceagoodusingfewerinputsthananotherproducerMeasuresthecostofagoodintermsoftheinputsrequiredtoproduceitPrincipleofcomparativeadvantageEachgoodshouldbeproducedbytheindividualthathasthesmalleropportunitycostofproducingthatgoodComparativeadvantageTheabilitytoproduceagoodataloweropportunitycostthananotherproducerPrincipleofcomparativeadvantageEachgoodshouldbeproducedbytheindividualthathasthesmalleropportunitycostofproducingthatgoodnote：Theseideawereallfollowingaprinciplethat"trade"canmakeeveryonebetter-off.Therefore,inacaseofinternationaltrade,twocountriesarewillingtoproduceproductthathasopportunitycost.Offcourse,ininternationalmarket,thelessopportuntiycost,themorecompletitveoftheprodcutorserivce.Ch4Supplyanddemand2018年2月10日19:35Marketsandcompetitiona.WhatisamarketAmarketisagroupsofbuyersandsellersofaparticulargoodorservice.Thebuyersasagroupdeterminethedemandfortheproduct,andthesellersasagroupdeterminethesupplyoftheproduct.Organizedmarket:wherehasmiddlemansetthepriceandtimeforexchangeofproduct.Suchasagriculturalcommodities.Usuallyhavefairlylargevalueofproductbeingexchanged.Lessorganizedmarket:Smalltownshopswheresellersandbuyersvaryfromtimetotime.Thepriceusuallydecidebysellersbutmostofthetimedrivenbycompetition.WhatiscompetitionCompetitivemarket:amarketinwhichtherearesomanybuyersandsomanysellersthateachhasanegligibleimpactonthemarketprice.Thereareconditionsmustbesatisfytobeaperfectcompetitionmarket.Thegoodsofferedforsaleareallexactlythesame,and(2)thebuyersandsellersaresonumerousthatnosinglebuyerorsellerhasanyinfluenceoverthemarketpriceDemanda.Thedemandcurve:therelationshipbet.PriceandquantitydemandedQuantitydemanded:anygoodistheamountofthegoodtatbuyersarewillingandabletopurchase.Lawofdemand:theclaimthat,otherthingsbeingequal,thequantitydemandedofagoodfallswhenthepriceofthegoodrises.MarketdemandVSindividualdemandMarketdemand=sum(individualdemand)c.ShiftsinthedemandcurveThemarketdemandcurveholdsotherthingsconstant,butitwasnotalwaysthecase.Theremaybesomethinghappenedthatwillchangethedemandcurve.Eitherincreasedemandthatwillshifttotherightordecreasedemandthatwillmakecurveshifttotheleft.Variablesthatwillaffectdemandcurveare.suchas1)IncomeNormalgoodvsinferiorgood:demandforagoodfallswhenincomefalls,thisiscallednormalgood.Demandforagoodriseswhenincomefalls,thisgoodcalledinferiorgood.Exampleofinferiorgoodmaybeabusrides.Whenpeople'sincomedecreasetheymaylesslikelytobuyarideortakecab,theytendtoridebus,becauseitscheap.2)pricesofrelatedgoodsComplements:whenafallinthepriceofonegoodraisesthedemandforanothergoodSubstitutes:twogoodsforwhichanincreaseinthepriceofoneleadstoanincreaseinthedemandfortheother3)TastesWhetheryourlikeornot.4)expectationsExpectationsaboutfuturemayalterwhatyoudonow.ifpeoplethinkingthatinthefuture,theirincomewillraise,thentheytendtobuymore.Thereforedemandincrease;inmyopinion,stockmarketisallaboutexpectations,whenbuyerthinkingstockpricewillgoup,theywillbuymore,thereforestockpricemaybeoverpriced.Othercasemayhavelowexpectations.5)numberofbuyers.Supplya.Thesupplycurve:Therelationshipbet.PriceandquantitysuppliedQuantitysupplied:theamountofagoodthatsellersarewillingandabletosell.Lawofsupply:theclaimthat,otherthingsbeingequal,thequantitysuppliedofagoodriseswhenthepriceofthegoodrises.MarketsupplyVSindividualsupplyMarketsupply=sum(individualssupply)c.ShiftsinthesupplycurveRaisesquantitysuppliedateveryprice,suchasafallinthepriceofsugar,shiftstheysupplycurvetotherightcalledincreaseinsupply.ChangethatreducesthequantitysuppliedateverypriceshiftsthesupplycurvetotheleftcalleddecreaseinsupplyTherearesomevariablesthatwillchangesupplycurve.Inputprices:Thisinotherword,costofproduction,whenpriceofproductiondecrease,producertendtoproducemoreproduct,becauseitbecomemoreprofitable,ifpriceofproductionincrease,theproducertendtoproducelessproduct,becauseitwasn'tasmuchasprofitable.Technology:Bettertechnologycanhelpproducemoreproductwithlesscost.Itfollowideaofinputprices.Expectations:4)numberofsellers\5.SupplyanddemandTogethera.Equilibrium:asituationinwhichthemarketpricehasreachedthelevelatwhichquantitysuppliedequalsquantitydemand.

Surplus:Asituationinwhichquantitysupplied>QdShortage:AsituationinwhichQuantitysupplied<QdThreestepstoanalyzingchangesinequilibriumWedecidewhethertheeventshiftsthesupplycurve,thedemandcurve,or,insomecases,bothcurves.Second,wedecidewhetherthecurveshiftstotherightortotheleft.Third,weusethesupply-and-demanddiagramtocomparetheinitialandthenewequilibrium,whichshowshowtheshiftaffectstheequilibriumpriceandquantityVI.Conclusion:HowpricesallocateResourceThischapterhasanalyzedsupplyanddemandinasinglemarket.OneoftheTenPrinciplesofEconomicsdiscussedinChapter1isthatmarketsareusuallyagoodwaytoorganizeeconomicactivitySimilarly,pricesdeterminewhoproduceseachgoodandhowmuchisproduced.SummaryCh5Elasticityanditsapplication2018年2月10日19:40Theelasticityofdemanda.ThepriceelasticityofdemandanditsdeterminatesElasticity:ameasureoftheresponsivenessofquantitydemandedorquantitysuppliedtoachangeinoneofitsdeterminates.Priceelasticityofdemand:howmuchthequantitydemandedofagoodorservicesrespondstoachangeinthepriceofthatgoodorservices.SomefactoriesthatcaneffectelasticityofdemandAvailabilityofclosesubstitutesNecessitiesversusluxuriesDefinitionofthemarket:narrowlydefinedmarketstendtohavemoreelasticdemandthanbroadlydefinedmarket.Timehorizon:goodstendtohavemoreelasticdemandoverlongertimehorizons.ComputingpriceelasticityofdemandPriceelasticityofdemand=percentagechangeinquantitydemand/percentagechangeinpriceThemidpointmethod:abetterwaytocalculatepercentagechangesandelasticities.Priceelasticityofdemand=(QPriceelasticityofdemand=(Q3-Q.14(Q2+層一PM—呂雙’ThevarietyofdemandcurvesDemandiselasticifpriceelasticityofdemandis>1Demandisinelasticifelasticityofdemandis<1Demandhasunitelasticityifpriceelasticityis=1TotalrevenueandthepriceelasticityofdemandForapriceincrease,ifdemandiselastic/resultindecreaseoftotalrevenue.E>1:%changeinQ>%changeinPTRdecreases:thefallinrevenuefromlowerQ>theincreaseinrevenuefromhigherPForapriceincrease,ifdemandisinelastic/resultinincreaseoftotalrevenue.E<1:%changeinQ<%changeinPTRincrease:thefallinrevenuefromlowerQ<theincreaseinrevenuefromhigherP.ElasticityandtotalrevenuealongalineardemandcurveOtherdemandelasticitiesb.Theelasticityofsupply?ThepriceelasticityofsupplyanditsdeterminatesPriceelasticityofsupply:HowmuchthequantitysuppliedofagoodrespondstoachangeinthepriceofthatgoodCalculationissameaselasticityindemand.Greaterpriceelasticityofsupplyifproducercaneasilychangethequantitytheycanbeproduce.Elasticityofsupplyisgreaterinthelongrunthanintheshortrun.ComputingthepriceelasticityofsupplyThevarietyofsupplycurvesThreeapplicationsofsupply,demand,andelasticityCangoodnewsforfarmingbebadnewsforfarmers?WhydidOPECfailtokeepthepriceofOilhigh?Doesdruginterdictionincreaseordecreasedrug-relatedcrime?ConclusionSummaryCh6Supply,Demand,andgovernmentpolicies2018年2月10日19:46i.ControlsonpricesPriceceiling:alegalmaximumonthepriceatwhichagoodcanbesoldPricefloor:AlegalminimumonthepriceatwhichagoodcanbesoldHowpriceceilingsaffectmarketoutcomesThepriceceilingwilleitherhavenoteffectontheequilibriumorcauseshortage.Theshortagewillledtoevenlesssupplyandbecomemoreunfairtowardpeoplewhowantthehousetolivemost.Becausesupplymayrenttothosewhopaymore,orwhoisrelatetohim/her.Itmaypotentiallydecreasethepriceofhouse.HowpricefloorsaffectmarketoutcomesEx:minimumwage.Thepricefloorswilleitherhavenotaffectontheequilibriumorcausessurplus.Inthecaseoflabormarket,thesurplusofsupplywillrisetheunemploymentrateandthreatpeoplewhoneedsworkmost.c.EvaluatingpricecontrolsTaxesTaxincidence:themannerinwhichtheburdenofataxissharedamongparticipantsinamarket.HowtaxesonsellersaffectmarketoutcomesInashort-run,taxputonsellerwilldecreasesupply.Becausetheinputoftheproductionhasbeenincrease.HowtaxesonbuyersaffectmarketoutcomesInshort-run,taxputonbuyerswilldecreasedemand.Inlong-runElasticityandtaxincidenceElasticityplayimportantroleinwhetherconsumerpayforincreaseintaxesorbuyerpayforincreaseintaxes.Forexample,ifaproductisaelastic,thechangeinpricewilllargelyeffectthequantity.Inthiscase,producerpaymoremoneyforincreaseintax,becausetheywon'tincreasethatmuchofmoneyiftheypaymoretaxes.Forainelasticproduct,thechangeinpricewillhavesmalleffectonthequantity.Inthiscase,theconsumerpaymoremoneyforincreaseintax,becauseproducerwillincreasepriceontheproductduetoincreaseintax,anditonlyhavelittleaffectontheirtotalrevenue.ConclusionCh7consumers,producersandtheefficiencyofmarket2018年2月10日19:48Inthischapter,wetakeupthetopicofwelfareeconomics,thestudyofhowtheallocationofresourcesaffectseconomicwellbeing.Webeginbyexaminingthebenefitsthatbuyersandsellersreceivefromengaginginmarkettransactions.Wethenexaminehowsocietycanmakethesebenefitsaslargeaspossible.Thisanalysisleadstoaprofoundconclusion:Inanymarket,theequilibriumofsupplyanddemandmaximizesthetotalbenefitsreceivedbyallbuyersandselle