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Chapter4ClassicalMacroeconomics Money PricesandInternetRate Inthischapter wewilldiscussthreequestions 1 theClassicalTheoryofAggregatePriceLevelDetermination2 theDeterminationoftheInternetrate3 theClassicalViewsonMonetaryandFiscalPolicy 4 1THEQUANTITYOFMONEY Intheclassicaltheory thequantityofmoneydeterminesaggregatedemondwhichinturndeterminesthepricelevel 4 1 1TheEquationofExchange4 1 2TheCambridgeApproachtotheQuantityTheory 4 1 1TheEquationofExchange Itisanidentityrelatingthevolumeoftransactionsatcurrentpricestothesupplyofmoneytimestheturnoverrateofeachdollar MVT PTT 4 1 Intheidentity VTisthethetransactionsvelocityofmoney whichmeasurestheaveragenumberoftimeseachdollarisusedintransationsduringtheperiod Itwasdeterminedbythepaymentshabitsandpaymenttechnologyofsociety MisthequantityofmoneyPTisthepriceindexfortheitemstradedTisthevolumeoftransactions whichincludesnotonlysalesandpurchasesofnewlyproducedgoodsbutalsoexchangesofpreviousproducedgoodsandfinancialassetsTherelationshipisanidentitybecauseoftheexpostdefinitionofvelocity Example Overagivenperiodthevalueoftranscationsincurrentdollars PTT were 3 600billionandthemoneysupply M were 300billion Howcanwedefinethetransactionsvelocity orturnoverrate ofmoneyasthenumberoftimestheaveragedollarwasusedintransactions VT PTT M 3 600 300 12 4 2 Anotherexpressionoftheexquation MV PY 4 3 Misthequantityofmoney Vistheincomevelocityofmoneyinvolvingcurrentoutput Pisthepriceindexforcurrentlyproducedoutput Yisthelevelofcurrentoutput Itfocusesonlyonincometransactions Thevariablesin 4 3 areeasiertomeasureandarecentraltoourconcerns 4 3 canalsobechangedintoV PY M 4 4 1 Theequilibriumlevelofvelocitywasdeterminedbyinstitutionalfactorsandcouldberegardedasfixedfortheshortrun 2 Outputisfixedfromthesupplyside soMV PY 4 5 VorP M 4 6 YWecanconclute Thequantityofmoneydeterminesthepricelevel 4 1 2TheCambridgeApproachtotheQuantityTheory Marchallbeganbyfocusingontheindividual sdecisionontheoptimalamountofmoneytohold Moneywillbeheldonlyinsofarasitsyieldintermsofconvenienceandsecuriyoutweightstheincomelostfromnotinvestinginproductiveactivityorthesatisfactionlostbynotsimplyusingthemoneytopurchasegoodstoconsume Md kPY 4 7 Mdisthemoneydemond Pisthepricelevel Yisthelevelofrealincome Thedemondformoneydependsontheleveloftransactions whichmaybesupposedtovaryclosedwithincome AsintheFisherianformulation theproportionofincomedependsonthepaymenthabitsofthesociety Kisassumedtobestable M Md KP 4 8 Intheshortrun kisfixedandrealoutput isdeterminedbysupplyconditions1M P 4 9 Comparedwith 4 5 V 1 k TheCambridgebridgefocuson1 thequantitytheoryasatheoryofthedemondformoney Theproportionalrelationshipbetweenthequantityofmoneyandthepricelevelresultedfromthefactthattheproportionofnominalincomepeoplewishedtoholdintheformofmoney k wasconstantandthelevelofrealoutputwasfixedbysupplyconditions 2 moneydemondleadstoananswertothequestionaboutthewaymoneyaffectsthepricelevel Anexcesssupplyofmoneyledtoincreaseddemondforcommoditiesandupwardpressureonthepricelevel 4 1 3TheClassicalAggregateDemondCurve FIGURE4 1FRGURE4 2 Ifmoneydemandexceeds fallshortof moneysupply therewillbeaspillovertothecommoditiesmarketasindividualstrytoreduce increase theirexpendituresoncommodities 4 1 3TheClassicalAggregateDemondCurve 4 2THECLASSICALTHEORYOFTHEINTERESTRATE Whatistheinterestingrate Itistheinterestingratethatguaranteesthatexogenouschangesintheparticularcomponentsofdemanddonotaffectaggregatedemond Whatistheequilibriuminterestrate Intheclassicaltheory itistherateatwhichtheamountoffundsindividualsdesiredtolendwasjustequaltotheamountothersdesiredtoborrow Theinterestratedependsonthefactorsthatdeterminethelevelsofbondsupplyandbonddemond 1 Intheclassicalsystem thesuppliersofbondswerethefirmsandthegovernment Foragivenexpectedprofitability investmentvariesinverselywiththeinterestrateandisalsoinfluencedbyexogenousshiftsintheexpectedprofitabilityofinvestmentprojects 2 Intheclassicalmodel onthedemandsideofthebondmarketaretheindividualsaverswhopurchasethebonds Savingwastakentobeapositivefunctionoftherateoftheinterest andwasademondforbonds Individualwilltakeadvantageofthismorefavorabletrade off theywillsavemoreathigherratesofinterest DeterminationoftheinterestrateisillustratedinFigure4 3 Inthediagram roistheequilibriuminterestrate therateofinterestthatequalsthedemondandsupplyfortheloanablefunds Theinterestrateplaysastabilizingroleintheclassicalsystem ascanbeseenbyexaminingtheeffectsofachangeintheexpectedprofitabilityofinvestmen TheFigure4 4isillustratestheeffectofthisautonomousdeclineininvestmentdemand Thestabilizingroleoftheinterestrateisimportanttotheclassicalsystem Itsadjustmentisthefirstlineofdefenseforthefullemployment 4 3POLICYIMPLICATIONSOFTHECLASSICALEQUILIBRIUMMODEL Inthissection weanalyzetheeffectsoffiscalandmonetarypolicyactionswithintheclassicalmodel Weconsidertheeffectsthatvariouspolicyshiftswillhaveonoutput employment thepricelevel andtheinterestrate 4 3 1FiscalPolicy Fiscalpolicyisthesettingofthefederalbudgetandthuscomprisesdecisionsongovernmentspendingandtaxation GovernmentSpending Howisthegovernmentspendingfinancedandincreased Fornow toavoidbringinginamonetarypolicychange weassumethatthemoneysupplyisfixed Wealsoassumethattaxcollectionsarefixed Theincreasedexpendituresarefinancedbysellingbondstothepublic whichwillnotaffecttheequilibriumvaluesofoutputorthepricelevel aswellastheemployment Figure4 5Itshowstheeffectintheloanablefundsmarketofanincreaseingovernmentspendingfinancedbyasaleofbondstothepublic Thefigureshowsthatthespendingfinancedbysellingbondstothepublicpushestheinterestrateupbyenoughto crowdout anequalamountofprivateexpenditure consumptionplusinvestment DistanceA DistanceBBecauseaggregatedemandisnotchanged thepricelevelisfixed Whataretheeffectsofanincreaseingovernmentspendingif alternatively thegovernmentprintsmoneytofinancethenewspending Agivenchangeinthemoneysupplyhasthesameeffectwhetheritenterstheeconomytofinanceanincreaseingovernmentspendingorinanothermanner Putdifferently theincreaseingovernmentspendinghasnoindependenteffectonaggregatedemand TaxPolicy Demand SideEffectsItisanalogoustothoseforgovernmentspending Ataxcutwillstimulateconsumption Ifthegovernmentsoldbondstoreplacetherevenueslostbythetaxcut thesamecrowing outprocesswouldfollow Theequilibriuminterestratewillrise investmentwillfall andtherewillalsobeariseinsaving Thetaxcuthavenoindependenteffectonaggregatedemand Supply SideEffectsIntheclassicalmodel suchachange supposethetaxcutisintheformofreducedincometaxrated willhaveanincentiveeffectonlaborsupply outputandemployment FIGURE4 6illustratestheeffectofacutinthemarginaltaxratewithintheclassicalmodel