alevel-economics-基础-讲义

A-LEVELMicroeconomicsbasic•Economicsisthestudyofhowsocietychoosestoallocateitsscarceresourcestotheproductionofgoodsandservicesinordertosatisfyunlimitedwants.•Humanwantsareunlimited,but•Resourcesarelimited(scarce)•Acentralproblemthereforeexists…wecallthistheproblemofSCARCITY43DefinitionofeconomicsEconomicsisthestudyofsociety’sdecisionsabout–production–consumption–allocationofscarceresourcesinordertosatisfyasmanyunlimitedwantsaspossible.54Twobranchesofeconomics•Microeconomicsisthebranchofeconomicsthatstudiesdecision-makingbyasingleindividual,household,firm,industryorlevelofgovernment.•Macroeconomicsisthebranchofeconomicsthatstudiesdecision-makingfortheeconomyasawhole.65MacroeconomicIssues–aggregatedemand,aggregatesupply–economicgrowth–unemployment–inflation–balanceoftrade–exchangerates76MicroeconomicIssues–demandandsupplydecisionsofwhattoproduce,howtoproduce,forwhomtoproduce–theconceptofopportunitycostbasedoncomparingwhatyouhavedecidedvswhatisthenextbestalternativeyouhavegivenup–rationaldecisionmakingbasedoncostvsbenefit;bestvalueformoney–weighingupmarginalcostsandmarginalbenefitsbasedoncomparingtheextrabenefitwiththeextracost–thesocialimplicationsofchoicesocietyi.e.takingintoconsiderationhowacertainchoicemayhaveanindirectcostonJohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaResources•Resourcesarethebasiccategoriesofinputsusedtoproducegoodsandservices.•Resourcescanalsobecalledthefactorsofproduction.JohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaThreecategoriesofresources•Land•Labour•CapitalJohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaResources:land•Anynaturalresourceprovidedbynatureusedintheprocessofproduction•Forexample:forests,minerals,wildlife,oil,rivers,lakes,oceans•Mayberenewableornon-renewableJohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaResources:labour•Thementalandphysicalcapacityofworkerstoproducegoodsandservices•Forexample:farmers,nurses,lawyersEntrepreneurshipisaspecialtypeoflabourthecreativeabilityofindividualstomanagethecombinationofresourcestoproduceproducts.JohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaEntrepreneurship•OrganisesandmanagestheresourcesneededtoproducegoodsandservicesJohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaResources:capital•Capitalisthephysicalplant,machineryandequipmentusedtoproduceothergoods.Thatis,human-madegoodsthatdonotdirectlysatisfyhumanwants,forexample:−Earlier:axe,bowandarrow−Now:buildings,productionequipment,software,factories.JohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaAnoteaboutfinancialcapital•Economistsdonotincludemoneyintheirdefinitionofcapitalmoneysimplygivesameasuretothevalueofassets.JohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaOpportunitycost•Thebestalternativesacrificedforachosenalternative•Opportunitycostappliestopersonal,groupandnationaldecision-making,forexample−Whatcouldyoubedoingifyouwerenotcurrentlystudying?−Howmanynewroadshavetobeforgoneifthegovernmentspendstaxrevenuesonhomelandsecurity?JohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaMarginalanalysis•Marginalanalysisexamineshowthecostsandbenefitschangeinresponsetoincrementalchangesinactions.•Anyadditionalactionbyanindividualorafirm,suchasbuyinganadditionalpairofshoesorincreasingproductionofaproductbyanadditionalunit,bringsadditionalcost.•ThecentralquestioninmarginalanalysisiswhethertheexpectedbenefitsofthatactionexceedtheaddedcostJohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaMarginalanalysis•Marginalanalysishelpsbusinessesandindividualsbalancethecostsandbenefitsofadditionalactions---whethertoproducemore,consumemore,orotherdecisions---anddeterminewhetherthebenefitswillexceedcosts,thusincreasingutility.JohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaMarginalanalysis•Marginalanalysisbenefitsgovernmentpolicymakers,aswell.•WeighingthecostsandbenefitscanhelpgovernmentofficialsdetermineifallocatingadditionalresourcestoaparticularpublicprogramwillgenerateadditionalbenefitsforthegeneralpublicJohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaShort-RunvLongRun•Short-Run:Atimeperiodinwhichatleastonefactorofproductionisfixed(i.e.cannotincreaseitsamount)itisnotdefinedintermsofnumberofdays/weeks)•LongRun:AtimeperiodlongenoughforallinputstobevariedItisnotadefinedperiodoftime;JohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaCostconcepts•Totalfixedcostsarecosts–thatdonotvaryasoutputvariesand–mustbepaidevenifoutputiszero.•Totalvariablecostsarecosts–thatarezerowhenoutputiszeroand–varyasoutputvaries.•Totalcostisthesumoffixedcostandvariablecost.TC=TFC+TVCJohnSloman,KeithNorris:PrinciplesofEconomics2e©2007PearsonEducationAustraliaTotalcostsNote:Thexandyaxisunitshereare