宏观经济学-帕金-ppt课件

1,WHATISECONOMICS?,Youarestudyingeconomicsatatimeofextraordinarychange.Yourlifewillbeshapedbythechallengesyoufaceandtheopportunitiesthatyoucreate.Buttofacethosechallengesandseizetheopportunitiestheypresent,youmustunderstandthepowerfulforcesatplay.Theeconomicsthatyoureabouttolearnwillbecomeyourmostreliableguide.,DefinitionofEconomics,Alleconomicquestionsarisebecausewewantmorethanwecanget.Ourinabilitytosatisfyallourwantsiscalledscarcity.Becausewefacescarcity,wemustmakechoices.Thechoiceswemakedependontheincentivesweface.Anincentiveisarewardthatencouragesanactionorapenaltythatdiscouragesanaction.,Economicsisthesocialsciencethatstudiesthechoicesthatindividuals,businesses,governments,andentiresocietiesmakeastheycopewithscarcityandtheincentivesthatinfluenceandreconcilethosechoices.Economicsdividesintomainparts:MicroeconomicsMacroeconomics,DefinitionofEconomics,Microeconomicsisthestudyofchoicesthatindividualsandbusinessesmake,thewaythosechoicesinteractinmarkets,andtheinfluenceofgovernments.Anexampleofamicroeconomicquestionis:Whyarepeoplebuyingmoree-booksandfewerhardcopybooks?Macroeconomicsisthestudyoftheperformanceofthenationalandglobaleconomies.Anexampleofamacroeconomicquestionis:WhyistheunemploymentrateintheUnitedStatessohigh?,DefinitionofEconomics,TwoBigEconomicQuestions,Twobigquestionssummarizethescopeofeconomics:Howdochoicesendupdeterminingwhat,how,andforwhomgoodsandservicesgetproduced?Whendochoicesmadeinthepursuitofself-interestalsopromotethesocialinterest?,What,How,andForWhom?Goodsandservicesaretheobjectsthatpeoplevalueandproducetosatisfyhumanwants.What?Agricultureaccountsforlessthan1percentoftotalU.S.production,manufacturedgoodsfor22percent,andservicesfor77percent.InChina,agricultureaccountsfor11percentoftotalproduction,manufacturedgoodsfor49percent,andservicesfor40percent.,TwoBigEconomicQuestions,TwoBigEconomicQuestions,Figure1.1showsthesenumbersfortheUnitedStatesandChina.ItalsoshowsthenumbersforBrazil.Whatdeterminesthesepatternsofproduction?HowdochoicesendupdeterminingthequantityofeachitemproducedintheUnitedStatesandaroundtheworld?,How?Goodsandservicesareproducedbyusingproductiveresourcesthateconomistscallfactorsofproduction.Factorsofproductionaregroupedintofourcategories:LandLaborCapitalEntrepreneurship,TwoBigEconomicQuestions,The“giftsofnature”thatweusetoproducegoodsandservicesareland.Theworktimeandworkeffortthatpeopledevotetoproducinggoodsandservicesislabor.Thequalityoflabordependsonhumancapital,whichistheknowledgeandskillthatpeopleobtainfromeducation,on-the-jobtraining,andworkexperience.Thetools,instruments,machines,buildings,andotherconstructionsthatbusinessesusetoproducegoodsandservicesarecapital.Thehumanresourcethatorganizesland,labor,andcapitalisentrepreneurship.,TwoBigEconomicQuestions,Figure1.2showsameasureofthegrowthofhumancapitalintheUnitedStatesoverthelastcenturythepercentageofthepopulationthathascompleteddifferentlevelsofeducation.Economicsexplainsthesetrends.,TwoBigEconomicQuestions,ForWhom?Whogetsthegoodsandservicesdependsontheincomesthatpeopleearn.Landearnsrent.Laborearnswages.Capitalearnsinterest.Entrepreneurshipearnsprofit.,TwoBigEconomicQuestions,CanthePursuitofSelf-InterestPromotetheSocialInterest?Everyday,311millionAmericansand6.9billionpeopleinothercountriesmakeeconomicchoicesthatresultinWhat,How,andForWhomgoodsandservicesareproduced.Doweproducetherightthingsintherightquantities?Doweuseourfactorsofproductioninthebestway?Dothegoodsandservicesgotothosewhobenefitmostfromthem?,TwoBigEconomicQuestions,Self-InterestYoumakechoicesthatareinyourself-interestchoicesthatyouthinkarebestforyou.SocialInterestChoicesthatarebestforsocietyasawholearesaidtobeinthesocialinterest.Socialinteresthastwodimensions:EfficiencyEquity,TwoBigEconomicQuestions,Efficiencyisachievedwhentheavailableresourcesareusedtoproducegoodsandservices:AtthelowestpossiblepriceandInquantitiesthatgivethegreatestpossiblebenefit.Equityisfairness,buteconomistshaveavarietyofviewsaboutwhatisfair.TheBigQuestionCanchoicesmadeinself-interestpromotethesocialinterest?,TwoBigEconomicQuestions,Fourtopicsthatgeneratediscussionandthatillustratetensionbetweenself-interestandsocialinterestareGlobalizationTheinformation-ageeconomyGlobalwarmingEconomicinstability,TwoBigEconomicQuestions,GlobalizationGlobalizationmeanstheexpansionofinternationaltrade,borrowingandlending,andinvestment.Globalizationisintheself-interestofconsumerswhobuylow-costimportedgoodsandservicesandintheself-interestofthemultinationalfirmsthatproduceinlow-costregionsandsellinhigh-priceregions.Butisglobalizationintheself-interestoflow-wageworkersinothercountriesandU.S.firmsthatcantcompetewithlow-costimports?Isglobalizationinthesocialinterest?,TwoBigEconomicQuestions,TheInformation-AgeEconomyThetechnologicalchangeofthepastfortyyearshasbeencalledtheInformationRevolution.Theinformationrevolutionhasclearlyservedyourself-interest:Ithasprovidedyourcell-phone,laptop,loadsofhandyapplications,andtheInternet.Ithasalsoservedtheself-interestofBillGatesofMicrosoftandGordonMooreofIntel,bothofwhomhaveseentheirwealthsoar.Butdidtheinformationrevolutionservethesocialinterest?,TwoBigEconomicQuestions,ClimateChangeEveryday,whenyoumakeself-interestedchoicestouseelectricityandgasoline,youcontributetocarbonemissions.Youleaveyourcarbonfootprint.Youcanlessenyourcarbonfootprintbywalking,ridingabike,takingacoldshower,orplantingatree.ButcaneachoneofusbereliedupontomakedecisionsthataffecttheEarthscarbon-dioxideconcentrationinthesocialinterest?,TwoBigEconomicQuestions,EconomicInstabilityBetween1993and2007,theU.S.andglobaleconomiesexpandedstrongly.IncomesintheUnitedStatesincreasedby30percentandincomesinChinatripled.ButinAugust2007,aperiodoffinancialstressbeganthatsoongrippedtheentireglobalfinancialsystem.Thechoicesofbankstoborrowandlendandthechoicesofpeopleandbusinesstolendtoandborrowfrombanksaremadeinself-interest.Doesthislendingandborrowingservethesocialinterest?,TwoBigEconomicQuestions,TheEconomicWayofThinking,Sixkeyideasdefinetheeconomicwayofthinking:Achoiceisatradeoff.Peoplemakerationalchoicesbycomparingbenefitsandcosts.Benefitiswhatyougainfromsomething.Costiswhatyoumustgiveuptogetsomething.Mostchoicesare“how-much”choicesmadeatthemargin.Choicesrespondtoincentives.,TheEconomicWayofThinking,AChoiceIsaTradeoffTheeconomicwayofthinkingplacesscarcityanditsimplication,choice,atcenterstage.Youcanthinkabouteverychoiceasatradeoffanexchangegivinguponethingtogetsomethingelse.OnSaturdaynight,willyoustudyorhavefun?Youcantstudyorhavefunatthesametime,soyoumustmakeachoice.Whateveryouchoose,youcouldhavechosensomethingelse.Yourchoiceisatradeoff.,TheEconomicWayofThinking,MakingaRationalChoiceArationalchoiceisonethatcomparescostsandbenefitsandachievesthegreatestbenefitovercostforthepersonmakingthechoice.Onlythewantsofthepersonmakingachoicearerelevanttodetermineitsrationality.Theideaofrationalchoiceprovidesananswertothefirstquestion:Whatgoodsandserviceswillbeproducedandinwhatquantities?Theansweris:Thosethatpeoplerationallychoosetobuy!,TheEconomicWayofThinking,Howdopeoplechooserationally?Theanswersturnonbenefitsandcosts.Benefit:WhatyouGainThebenefitofsomethingisthegainorpleasurethatitbringsandisdeterminedbypreferencesPreferencesarewhatapersonlikesanddislikesandtheintensityofthosefeelings.,TheEconomicWayofThinking,Cost:WhatyouMustGiveUpTheopportunitycostofsomethingisthehighest-valuedalternativethatmustbegivenuptogetit.WhatisyouropportunitycostofgoingtoanAC/DCconcert?Opportunitycosthastwocomponents:1.ThethingsyoucantaffordtobuyifyoupurchasetheAC/DCticket.2.Thethingsyoucantdowithyourtimeifyouspendattheconcert.,HowMuch?ChoosingattheMarginYoucanallocatethenexthourbetweenstudyingandinstantmessagingyourfriends.Thechoiceisnotallornothing,butyoumustdecidehowmanyminutestoallocatetoeachactivity.Tomakethisdecision,youcomparethebenefitofalittlebitmorestudytimewithitscostyoumakeyourchoiceatthemargin.,TheEconomicWayofThinking,Tomakeachoiceatthemargin,youevaluatetheconsequencesofmakingincrementalchangesintheuseofyourtime.Thebenefitfrompursuinganincrementalincreaseinanactivityisitsmarginalbenefit.Theopportunitycostofpursuinganincrementalincreaseinanactivityisitsmarginalcost.Ifthemarginalbenefitfromanincrementalincreaseinanactivityexceedsitsmarginalcost,yourrationalchoiceistodomoreofthatactivity.,TheEconomicWayofThinking,ChoicesRespondtoIncentivesAchangeinmarginalcostorachangeinmarginalbenefitchangestheincentivesthatwefaceandleadsustochangeourchoice.Thecentralideaofeconomicsisthatwecanpredicthowchoiceswillchangebylookingatchangesinincentives.Incentivesarealsothekeytoreconcilingself-interestandthesocialinterest.,TheEconomicWayofThinking,Economics:ASocialScienceandPolicyTool,EconomistasSocialScientistEconomistsdistinguishbetweentwotypesofstatement:WhatispositivestatementsWhatoughttobenormativestatementsApositivestatementcanbetestedbycheckingitagainstfacts.Anormativestatementexpressesanopinionandcannotbetested.,U