宏观经济学曼昆版PPT

Copyright©2004South-Western27TheBasicToolsofFinanceCopyright©2004South-WesternInthischapter,wearegoingtostudy…1.Theconceptofpresentvalueanditscalculation2.Waysofmanagingrisks3.Diversificationofidiosyncraticrisk4.Fundamentalanalysis5.EfficientmarketshypothesisCopyright©2004South-Western•Financeisthefieldthatstudieshowpeoplemakedecisionsregardingtheallocationofresourcesovertimeandthehandlingofrisk.Copyright©2004South-WesternPRESENTVALUE:MEASURINGTHETIMEVALUEOFMONEY•Presentvaluereferstotheamountofmoneytodaythatwouldbeneededtoproduce,usingprevailinginterestrates,agivenfutureamountofmoney.Copyright©2004South-WesternPRESENTVALUE:MEASURINGTHETIMEVALUEOFMONEY•Theconceptofpresentvaluedemonstratesthefollowing:•Receivingagivensumofmoneyinthepresentispreferredtoreceivingthesamesuninthefuture.•Inordertocomparevaluesatdifferentpointsintime,comparetheirpresentvalues.•Firmsundertakeinvestmentprojectsifthepresentvalueoftheprojectexceedsthecost.Copyright©2004South-WesternPRESENTVALUE:MEASURINGTHETIMEVALUEOFMONEY•Ifristheinterestrate,thenanamountXtobereceivedinNyearshaspresentvalueof:X/(1+r)NCopyright©2004South-WesternPRESENTVALUE:MEASURINGTHETIMEVALUEOFMONEY•FutureValue•Theamountofmoneyinthefuturethatanamountofmoneytodaywillyield,givenprevailinginterestrates,iscalledthefuturevalue.Copyright©2004South-WesternFYI:Ruleof70•Accordingtotheruleof70,ifsomevariablegrowsatarateofxpercentperyear,thenthatvariabledoublesinapproximately70/xyears.Copyright©2004South-WesternMANAGINGRISK•Apersonissaidtoberiskaverseifsheexhibitsadislikeofuncertainty.Copyright©2004South-WesternMANAGINGRISK•Individualscanreduceriskchoosinganyofthefollowing:•Buyinsurance•Diversify•AcceptalowerreturnontheirinvestmentsFigure1RiskAversionWealth0UtilityCurrentwealth$1,000gain$1,000lossUtilitylossfromlosing$1,000Utilitygainfromwinning$1,000Copyright©2004South-WesternCopyright©2004South-WesternTheMarketsforInsurance•Onewaytodealwithriskistobuyinsurance.•Thegeneralfeatureofinsurancecontractsisthatapersonfacingariskpaysafeetoaninsurancecompany,whichinreturnagreestoacceptallorpartoftherisk.Copyright©2004South-WesternDiversificationofIdiosyncraticRisk•Diversificationreferstothereductionofriskachievedbyreplacingasingleriskwithalargenumberofsmallerunrelatedrisks.Copyright©2004South-WesternDiversificationofIdiosyncraticRisk•Idiosyncraticriskistheriskthataffectsonlyasingleperson.Theuncertaintyassociatedwithspecificcompanies.Copyright©2004South-WesternDiversificationofIdiosyncraticRisk•Aggregateriskistheriskthataffectsalleconomicactorsatonce,theuncertaintyassociatedwiththeentireeconomy.•Diversificationcannotremoveaggregaterisk.Figure2DiversificationNumberofStocksinPortfolio49(Morerisk)(Lessrisk)2001468102040Risk(standarddeviationofportfolioreturn)AggregateriskIdiosyncraticrisk30Copyright©2004South-WesternCopyright©2004South-WesternDiversificationofIdiosyncraticRisk•Peoplecanreduceriskbyacceptingalowerrateofreturn.Figure3TheTradeoffbetweenRiskandReturnRisk(standarddeviation)051015208.33.1Return(percentperyear)50%stocks25%stocksNostocks100%stocks75%stocksCopyright©2004South-WesternCopyright©2004South-WesternASSETVALUATION•Fundamentalanalysisisthestudyofacompany’saccountingstatementsandfutureprospectstodetermineitsvalue.Copyright©2004South-WesternASSETVALUATION•Peoplecanemployfundamentalanalysistotrytodetermineifastockisundervalued,overvalued,orfairlyvalued.•Thegoalistobuyundervaluedstock.Copyright©2004South-WesternEfficientMarketsHypothesis•Theefficientmarketshypothesisisthetheorythatassetpricesreflectallpubliclyavailableinformationaboutthevalueofanasset.Copyright©2004South-WesternEfficientMarketsHypothesis•Amarketisinformationallyefficientwhenitreflectsallavailableinformationinarationalway.•Ifmarketsareefficient,theonlythinganinvestorcandoisbuyadiversifiedportfolioCopyright©2004South-WesternCASESTUDY:RandomWalksandIndexFunds•Randomwalkreferstothepathofavariablewhosechangesareimpossibletopredict.•Ifmarketsareefficient,allstocksarefairlyvaluedandnostockismorelikelytoappreciatethananother.Thusstockpricesfollowarandomwalk.Copyright©2004South-WesternSummary•Becausesavingscanearninterest,asumofmoneytodayismorevaluablethanthesamesumofmoneyinthefuture.•Apersoncancomparesumsfromdifferenttimesusingtheconceptofpresentvalue.•Thepresentvalueofanyfuturesumistheamountthatwouldbeneededtoday,givenprevailinginterestrates,toproducethefuturesum.Copyright©2004South-WesternSummary•Becauseofdiminishingmarginalutility,mostpeopleareriskaverse.•Risk-aversepeoplecanreduceriskusinginsurance,throughdiversification,andbychoosingaportfoliowithlowerriskandlowerreturns.•Thevalueofanasset,suchasashareofstock,equalsthepresentvalueofthecashflowstheownerofthesharewillreceive,includingthestreamofdividendsandthefinalsaleprice.Copyright©2004South-WesternSummary•Accordingtotheefficientmarketshypothesis,financialmarketsprocessavailableinformationrationally,soastockpricealwaysequalsthebestestimateofthevalueoftheunderlyingbusiness.•Someeconomistsquestiontheefficientmarketshypothesis,however,andbelievethatirrationalpsych