最新北大ceer笔记9课件PPT.ppt 81页

'北大ceer笔记9 StructurePresentandfuturevaluesIntertemporalbudgetconstraintPreferencesforintertemporalconsumptionIntertemporalchoiceComparativestaticsValuingsecurities IntertemporalChoicePersonsoftenreceiveincomein“lumps”;e.g.monthlysalary.Howisalumpofincomespreadoverthefollowingmonth(savingnowforconsumptionlater)?Orhowisconsumptionfinancedbyborrowingnowagainstincometobereceivedattheendofthemonth? PresentValue（现值）Supposeyoucanpaynowtoobtain$1atthestartofnextperiod.Whatisthemostyoushouldpay?$1?No.Ifyoukeptyour$1nowandsaveditthenatthestartofnextperiodyouwouldhave$(1+r)>$1,sopaying$1nowfor$1nextperiodisabaddeal. PresentValueQ:Howmuchmoneywouldhavetobesavednow,inthepresent,toobtain$1atthestartofthenextperiod?A:$msavednowbecomes$m(1+r)atthestartofnextperiod,sowewantthevalueofmforwhichm(1+r)=1Thatis,m=1/(1+r),thepresent-valueof$1obtainedatthestartofnextperiod. PresentValueThepresentvalueof$1availableatthestartofthenextperiodisAndthepresentvalueof$mavailableatthestartofthenextperiodis PresentValueE.g.,ifr=0.1thenthemostyoushouldpaynowfor$1availablenextperiodisAndifr=0.2thenthemostyoushouldpaynowfor$1availablenextperiodis TheIntertemporalChoiceProblemLetm1andm2beincomesreceivedinperiods1and2.Letc1andc2beconsumptionsinperiods1and2.Letp1andp2bethepricesofconsumptioninperiods1and2. TheIntertemporalChoiceProblemTheintertemporalchoiceproblem:Givenincomesm1andm2,andgivenconsumptionpricesp1andp2,whatisthemostpreferredintertemporalconsumptionbundle(c1,c2)?Forananswerweneedtoknow:theintertemporalbudgetconstraintintertemporalconsumptionpreferences. TheIntertemporalBudgetConstraintTostart,let’signorepriceeffectsbysupposingthatp1=p2=$1. TheIntertemporalBudgetConstraintSupposethattheconsumerchoosesnottosaveortoborrow.Q:Whatwillbeconsumedinperiod1?A:c1=m1.Q:Whatwillbeconsumedinperiod2?A:c2=m2. TheIntertemporalBudgetConstraintc1c2m2m100 TheIntertemporalBudgetConstraintc1c2So(c1,c2)=(m1,m2)istheconsumptionbundleiftheconsumerchoosesneithertosavenortoborrow.m2m100 TheIntertemporalBudgetConstraintNowsupposethattheconsumerspendsnothingonconsumptioninperiod1;thatis,c1=0andtheconsumersavess1=m1.Theinterestrateisr.Whatnowwillbeperiod2’sconsumptionlevel? TheIntertemporalBudgetConstraintPeriod2incomeism2.Savingsplusinterestfromperiod1sumto(1+r)m1.Sototalincomeavailableinperiod2ism2+(1+r)m1.Soperiod2consumptionexpenditureis TheIntertemporalBudgetConstraintPeriod2incomeism2.Savingsplusinterestfromperiod1sumto(1+r)m1.Sototalincomeavailableinperiod2ism2+(1+r)m1.Soperiod2consumptionexpenditureis TheIntertemporalBudgetConstraintc1c2m2m100thefuture-valueoftheincomeendowment TheIntertemporalBudgetConstraintc1c2m2m100istheconsumptionbundlewhenallperiod1incomeissaved. TheIntertemporalBudgetConstraintNowsupposethattheconsumerspendseverythingpossibleonconsumptioninperiod1,soc2=0.Whatisthemostthattheconsumercanborrowinperiod1againstherperiod2incomeof$m2?Letb1denotetheamountborrowedinperiod1. TheIntertemporalBudgetConstraintOnly$m2willbeavailableinperiod2topayback$b1borrowedinperiod1.Sob1(1+r)=m2.Thatis,b1=m2/(1+r).Sothelargestpossibleperiod1consumptionlevelis TheIntertemporalBudgetConstraintOnly$m2willbeavailableinperiod2topayback$b1borrowedinperiod1.Sob1(1+r)=m2.Thatis,b1=m2/(1+r).Sothelargestpossibleperiod1consumptionlevelis TheIntertemporalBudgetConstraintc1c2m2m100istheconsumptionbundlewhenallperiod1incomeissaved.thepresent-valueoftheincomeendowment TheIntertemporalBudgetConstraintc1c2m2m100istheconsumptionbundlewhenperiod1borrowingisasbigaspossible.istheconsumptionbundlewhenperiod1savingisaslargeaspossible. TheIntertemporalBudgetConstraintSupposethatc1unitsareconsumedinperiod1.Thiscosts$c1andleavesm1-c1saved.Period2consumptionwillthenbe TheIntertemporalBudgetConstraintSupposethatc1unitsareconsumedinperiod1.Thiscosts$c1andleavesm1-c1saved.Period2consumptionwillthenbewhichisíïïíîììîslopeintercept TheIntertemporalBudgetConstraintc1c2m2m100slope=-(1+r) TheIntertemporalBudgetConstraintc1c2m2m100SavingBorrowingslope=-(1+r) TheIntertemporalBudgetConstraintisthe“future-valued”formofthebudgetconstraintsincealltermsareinperiod2values.Thisisequivalenttowhichisthe“present-valued”formoftheconstraintsincealltermsareinperiod1values.Asrrises,itisasifperiod1consumptionismoreexpensiveorperiod2consumptioncheaper. TheIntertemporalBudgetConstraintIfweallowforinflationordeflation,thenpricesofconsumptiongoodsmaybedifferentintwoperiods.Usep1andp2todenotepricesforconsumptioninperiods1and2.Howdoesthisaffectthebudgetconstraint? IntertemporalChoiceGivenherendowment(m1,m2)andpricesp1,p2whatintertemporalconsumptionbundle(c1*,c2*)willbechosenbytheconsumer?Maximumpossibleexpenditureinperiod2issomaximumpossibleconsumptioninperiod2is IntertemporalChoiceSimilarly,maximumpossibleexpenditureinperiod1issomaximumpossibleconsumptioninperiod1is IntertemporalChoiceFinally,ifc1unitsareconsumedinperiod1thentheconsumerspendsp1c1inperiod1,leavingm1-p1c1savedforperiod1.Availableincomeinperiod2willthenbeso IntertemporalChoicerearrangedisThisisthe“future-valued”formofthebudgetconstraintsincealltermsareexpressedinperiod2values.Equivalenttoitisthe“present-valued”formwherealltermsareexpressedinperiod1values. TheIntertemporalBudgetConstraintc1c2m2/p2m1/p100 TheIntertemporalBudgetConstraintc1c2m2/p2m1/p100 TheIntertemporalBudgetConstraintc1c2m2/p2m1/p100 TheIntertemporalBudgetConstraintc1c2m2/p2m1/p100Slope= TheIntertemporalBudgetConstraintc1c2m2/p2m1/p100SavingBorrowingSlope= IntertemporalPreferencesExtremecasesPerfectsubstitutePerfectcomplementIntermediatecaseofwell-behavedpreferences IntertemporalPreferencesc1c2 IntertemporalChoicec1m2/p2m1/p100Theconsumersaves.c2c1m2/p2m1/p1Theconsumerborrows.c2 ComparativeStaticsInterestraterisesorfallsPriceinflation ComparativeStaticsTheslopeofthebudgetconstraintisTheconstraintbecomesflatteriftheinterestraterfalls.Theconstraintbecomessteeperiftheinterestraterrises. ComparativeStaticsc1c2m2/p2m1/p1slope= ComparativeStaticsc1c2m2/p2m1/p100slope=Theconsumersaves. ComparativeStaticsc1c2m2/p2m1/p100slope=Adecreaseintheinterestrate“flattens”thebudgetconstraint.Theconsumersaves. ComparativeStaticsc1c2m2/p2m1/p100slope=Iftheconsumerchoosetoremainalenderthenherwelfareisreducedbyalowerinterestrate.Signonsavingisambiguous.Theconsumerinitiallysaves. ComparativeStaticsc2c1m2/p2m1/p100slope=Theconsumerborrows. ComparativeStaticsc1c2m2/p2m1/p100slope=Afallintheinterestrate“flattens”thebudgetconstraint.Theconsumerborrows. ComparativeStaticsc1c2m2/p2m1/p100slope=Theconsumerwillremainaborrower.Welfareisincreasedbyalowerinterestrate.Willborrowmore.Theconsumerborrows. BorroworLendafteraChangeinInterestRate?UseWARP.Differenteffectsforrisinginterestrates(seetextbookforanalysisofrisinginterestrates). EffectonConsumption(Saving)?SlutskyEquation(?)(-)(?)(+)Iflender,(m-c)<0,totaleffectisnegative.Ifborrower,(m-c)>0,totaleffectisambiguous. PriceInflationDefinetheinflationratebypwhereForexample,p=0.2means20%inflation,andp=1.0means100%inflation. PriceInflationWelosenothingbysettingp1=1sothatp2=1+p.Thenwecanrewritethebudgetconstraintas PriceInflationrearrangestosotheslopeoftheintertemporalbudgetconstraintis PriceInflationWhentherewasnopriceinflation(p1=p2=1)theslopeofthebudgetconstraintwas-(1+r).Now,withpriceinflation,theslopeofthebudgetconstraintis-(1+r)/(1+p).Thiscanbewrittenasrisknownastherealinterestrate（实际利率）.riscalledthenominalinterestrate（名义利率）. RealInterestRategivesForlowinflationrates(p»0),r»r-p.Forhigherinflationratesthisapproximationbecomespoor. RealInterestRate ComparativeStaticsTheslopeofthebudgetconstraintisTheconstraintbecomesflatteriftheinflationrateprises.Theeffectisthesameasfalling(nominal)interestrate.Bothhavetheeffectofdecreasingtherealrateofinterest.Earliercomparativestaticanalysesapply. ValuingSecurities（证券）Afinancialsecurity（金融证券）isafinancialinstrumentthatpromisestodeliveranincomestream.E.g.;asecuritythatpays$m1attheendofyear1,$m2attheendofyear2,and$m3attheendofyear3.Whatisthemostthatshouldbepaidnowforthissecurity? ValuingSecuritiesThesecurityisequivalenttothesumofthreesecurities;thefirstpaysonly$m1attheendofyear1,thesecondpaysonly$m2attheendofyear2,andthethirdpaysonly$m3attheendofyear3. ValuingSecuritiesThePVof$m1paid1yearfromnowisThePVof$m2paid2yearsfromnowisThePVof$m3paid3yearsfromnowisThePVofthesecurityistherefore ValuingBonds（债券）Abondisaspecialtypeofsecuritythatpaysafixedamount$xforTyears(itsmaturitydate)andthenpaysitsfacevalue（面值）$F.Whatisthemostthatshouldnowbepaidforsuchabond? ValuingBonds ValuingBondsSupposeyouwinaStatelottery.Theprizeis$1,000,000butitispaidover10yearsinequalinstallmentsof$100,000each.Whatistheprizeactuallyworth? ValuingBondsistheactual(present)valueoftheprize. ValuingConsolsAconsolisabondwhichneverterminates,paying$xperperiodforever.Whatisaconsol’spresent-value? ValuingConsols ValuingConsolsSolvingforPVgives ValuingConsolsE.g.ifr=0.1nowandforeverthenthemostthatshouldbepaidnowforaconsolethatprovides$1000peryearis 6大差距你与职场精英之间的6大差距 完成有效完成工作是为了完成任务、不考虑好的结果工作是为了好结果内心不是非常接受这个工作、不开心主动跟领导沟通，同事协助不主动找领导沟通工作是表现自己能力的机会没有为了好的结果寻求好方法做好一份工作是一次很好的学习机会工作马虎，不细致为自己做，不是为了老板做感觉的是压力不是动力结果好事评判工作好的标准内心觉得是工作不是机会成就工作成就自己 被动工作主动工作等着领导指派工作领导指派的工作第一时间完成领导安排的工作等着领导催主动跟领导要工作没有紧迫感主动协助同事完成工作工作开心最重要公司重要活动主要参与并承担责任最好一天没工作对工作负责有点压力就受不了主动沟通，客户，同事，领导得过且过勤奋、努力、上进 抱怨担当为什么他那么轻松、为什么我老加班老板这件事情我负责为什么我工作这么多老板，这个工作我能做为什么他不配和我老板公司有压力，我得奖金可以晚点发老板为什么对我意见这么大老板这个客户很重要，我想去拜访一次为什么我得工资这么低这个月业绩我一定想办法完成他为什么能拿奖金这件事，老板你不用操心了指标给我这么高跟着公司一起成长 员工思维老板思维只要我开心就好一切为公司着想我是来打工的公司发展好，我才会好公司赚不赚钱跟我没关系主动、积极、乐观、责任、担当公司发展跟我没关系小我，事大，做好每一件工作早九晚五，下班了，别找我大局观、跟同事关系好老板，这事不应该是我做的关注行业趋势，品类趋势本位主义以公司为荣 我为中心团队为中心我是有个性有脾气的团队利益至上这件事情我很不爽脾气是假的，成事才是真的我的想法是这样这样的有牺牲精神、奉献精神老板，我不认可这件事情第一时间融入团队我觉得太累了敢于承担责任休假去了，年假为什么不休做事有头有尾这件事情跟我无关不抱怨，少脾气 不求上进追求发展能拿到工资就好感觉自己懂得太少，每天学习我不想太累这个我想试试，我相信能做好这个事情别找我，不是我的职责事业为重，娱乐为轻这个我搞不懂，也学不会敢于挑大梁一看书就犯困工作是为了学习，积累经验我已经做完了，结果跟我没关系目标清晰，执行力强随便你们，你们看着办不懂就问，不会就学 转化能力荣誉出品'