清云科技大學國際企業(yè)經(jīng)營系

1、 0清雲(yún)科技大學國際企業(yè)經(jīng)營系A(chǔ)ggregate Demand and Output in the Short Run 1清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 1未經(jīng)許可請勿翻印Modeling FluctuationsuGoal of this chapteruTo develop a model of how recessions and expansions may arise from fluctuations in aggregate spending following Keynes 發(fā)展一套模型，來說明總合支出的變動發(fā)展一套模型，來說明總合支出的變動如何影響衰退與擴張。如何影

2、響衰退與擴張。uBasic Keynesian model or the Keynesian Cross 簡單凱因斯模型簡單凱因斯模型 2清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 2未經(jīng)許可請勿翻印AssumptionsuAggregate demand fluctuates 總合需求波動總合需求波動 uTotal planned spending changes 總計畫支出金額改變總計畫支出金額改變 3清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 3未經(jīng)許可請勿翻印AssumptionsuIn the short run, firms meet the demand for their prod

3、ucts at present pricesuDo not respond to every change in demand by changing their pricesuSet a price for some period and meet the demand at that priceuProduce just enough to satisfy their customers 4清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 4未經(jīng)許可請勿翻印Meet the DemanduMenu costs: The costs of changing pricesuFirms do not c

4、hange their prices frequentlyuOr, in the short runuFirms will eventually change prices if there is a large imbalance between sales and potential output 5清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 5未經(jīng)許可請勿翻印Aggregate DemanduAggregate demand (AD)uTotal planned spending on final goods and services 對最終財貨與勞務(wù)的總計畫支出對最終財貨與勞務(wù)的總計畫支

5、出uFour componentsuConsumer expenditure (C)uInvestment (I)uGovernment purchases (G)uNet exports (NX) 6清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 6未經(jīng)許可請勿翻印InvestmentuInvestmentuSpending by firms on final goods and services 廠商購買的最終財貨與勞務(wù)廠商購買的最終財貨與勞務(wù)uBusiness fixed investment 商業(yè)固定投資商業(yè)固定投資uNew machinery and new factories 新機器與新

6、工廠新機器與新工廠uResidential investment 住宅投資住宅投資uNew homes and apartment buildings 新房屋與公寓建築新房屋與公寓建築uInventory investment 存貨投資存貨投資uUnsold inventories 未售存貨未售存貨 7清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 7未經(jīng)許可請勿翻印Unplanned InvestmentuSuppose a firms actual sales are less then expecteduThe extra inventory becomes part of actual in

7、vestment uActual investment is greater than planned investmentuI IpuIp planned investment 預擬投資預擬投資uI actual investment 實際投資實際投資 u當銷售量低於預期當銷售量低於預期存貨增加存貨增加 實際投資大於預擬投資實際投資大於預擬投資 8清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 8未經(jīng)許可請勿翻印Ex 25.1 實際與預擬投資uFN風箏公司本年度生產(chǎn)計畫如下：風箏公司本年度生產(chǎn)計畫如下：u生產(chǎn)價值生產(chǎn)價值5,000,000的風箏的風箏u預計銷售預計銷售4,800,000的風箏的風箏

8、u預計保留預計保留200,000的存貨的存貨uFN當年度添購當年度添購1,000,000的機器設(shè)備的機器設(shè)備uFN風箏公司實際銷售風箏公司實際銷售$4,600,000的風箏的風箏u試問試問FN風箏公司當年度的實際投資風箏公司當年度的實際投資I ？ 預擬投資預擬投資Ip？ 9清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 9未經(jīng)許可請勿翻印小組討論：Ex 25.1 實際與預擬投資uFN風箏公司本年度生產(chǎn)計畫如下：風箏公司本年度生產(chǎn)計畫如下：u生產(chǎn)價值生產(chǎn)價值5,000,000的風箏的風箏u預計銷售預計銷售4,800,000的風箏的風箏u預計保留預計保留200,000的存貨的存貨uFN當年度添購當年度添

9、購1,000,000的機器設(shè)備的機器設(shè)備u問題問題1：若：若FN風箏公司實際銷售風箏公司實際銷售$4,800,000的風箏的風箏 試問試問FN風箏公司當年度的實際投資風箏公司當年度的實際投資I ？ 預擬投資預擬投資Ip？u問題問題2：若：若FN風箏公司實際銷售風箏公司實際銷售$5,000,000的風箏的風箏 試問試問FN風箏公司當年度的實際投資風箏公司當年度的實際投資I ？ 預擬投資預擬投資Ip？ 10清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 10未經(jīng)許可請勿翻印Planned vs. ActualuAggregate demand is planned spendinguPlanned ma

10、y differ from actual for firms 廠商的預擬投資與實際投資不同廠商的預擬投資與實際投資不同uFor households, governments, and foreign purchasers we can reasonably assume that actual equals planned 家戶、政府與國外部門的實際值預擬值家戶、政府與國外部門的實際值預擬值 11清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 11未經(jīng)許可請勿翻印Definition of Aggregate DemanduAggregate demand （expenditure）equals

11、the economys total planned spendingAD = C + Ip + G + NX 12清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 12未經(jīng)許可請勿翻印ConsumptionuC is nearly 2/3rds of ADuMany determinants of consumption spendinguPrices, incomes, tastes, etc.uDisposable income 可支配所得可支配所得uNational income (Y) minus net taxes (T)udisposable income consumption (C)

12、 可支配所得上升可支配所得上升消費上升消費上升 13清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 13未經(jīng)許可請勿翻印Consumption FunctionCCc YT()Cu constant term capturing factors other than disposable income 不受可支配所得影響的固定項（自發(fā)性支出）不受可支配所得影響的固定項（自發(fā)性支出）uc is the MPC (Marginal propensity to consume) 邊際消費傾向邊際消費傾向uThe amount by which consumption rises when disposab

13、le income rises by $1 可支配所得增加可支配所得增加1時，消費的增加量時，消費的增加量uWe assume that 0 c C AD 18清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 18未經(jīng)許可請勿翻印AD and OutputpAD C IG NX uFor now assume that Ip, G, NX, and T are fixed, so thatTTXNNXGGIIp()pADCc YTIGNX 19清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 19未經(jīng)許可請勿翻印AD and OutputuSubstituting and rearranging,()ADCc

14、 YTIGNXuShows if Y increases by one unit, then AD increases by c unitsuPositive relationship between Y and ADuc is the MPC()ADCcTIGNXcY 20清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 20未經(jīng)許可請勿翻印Autonomous ADuAutonomous aggregate demand 自發(fā)性總合需求自發(fā)性總合需求uThe portion of aggregate demand that is determined outside the model 總合需求中

15、，由模型以外因素決定的部分總合需求中，由模型以外因素決定的部分()CcTIGNX 21清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 21未經(jīng)許可請勿翻印Induced ADuInduced aggregate demand 誘發(fā)性總合需求誘發(fā)性總合需求uThe portion of aggregate demand that is determined within the model cY總合需求中，由模型以內(nèi)因素決定的部分總合需求中，由模型以內(nèi)因素決定的部分 22清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 22未經(jīng)許可請勿翻印Ex25.2： AD and Outputu寫出總需求函數(shù)寫出總需求函

16、數(shù)u自發(fā)性總合需求？自發(fā)性總合需求？ 誘發(fā)性總合需求？誘發(fā)性總合需求？u邊際消費傾向？邊際消費傾向？ 23清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 23未經(jīng)許可請勿翻印小組討論：P684習題3u寫出總需求函數(shù)寫出總需求函數(shù)u自發(fā)性總合需求？自發(fā)性總合需求？ 誘發(fā)性總合需求？誘發(fā)性總合需求？u邊際消費傾向？邊際消費傾向？ 24清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 24未經(jīng)許可請勿翻印Fig. 13.3 Determination of Short-Run Equilibrium Output (Keynesian Cross) 25清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 25未經(jīng)許可請勿翻

17、印Numerical SR EquilibriumuUsing Example 25.2 and Table 25.1uIf output Y was 4,000uFirms are not producing enoughuInventories are being depleted, I IpuFirms respond by decreasing productionuSR equilibrium occurs when Y = 4,800 26清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 26未經(jīng)許可請勿翻印SR Equilibrium OutputuShort-run equilibri

18、um output 短期均衡產(chǎn)出短期均衡產(chǎn)出uThe level of output at which output Y equals aggregate demand AD 短期均衡條件為短期均衡條件為YAD 27清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 27未經(jīng)許可請勿翻印Ex25.2:SR Equilibrium OutputuShort-run equilibrium output 短期均衡產(chǎn)出短期均衡產(chǎn)出uAD=960+0.8YuY=ADuY=960+0.8Y 0.2Y=960 Y=4800 28清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 28未經(jīng)許可請勿翻印Fig. 13.3 Det

19、ermination of Short-Run Equilibrium Output (Keynesian Cross) 29清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 29未經(jīng)許可請勿翻印小組討論：P684習題3u畫出總需求函數(shù)？畫出總需求函數(shù)？u短期均衡條件短期均衡條件u計算短期均衡產(chǎn)出？計算短期均衡產(chǎn)出？ 30清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 30未經(jīng)許可請勿翻印小組討論：P684習題6u計算總需求函數(shù)計算總需求函數(shù)u畫出總需求函數(shù)？畫出總需求函數(shù)？u短期均衡條件短期均衡條件u計算短期均衡產(chǎn)出？計算短期均衡產(chǎn)出？ 31清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 31未經(jīng)許可請勿翻印A

20、D and GapsuUsing Example 25.2 and adding the assumption that potential output also equals 4,800 假設(shè)潛在產(chǎn)出為假設(shè)潛在產(chǎn)出為4800u自發(fā)性消費降低為自發(fā)性消費降低為610 短期均衡產(chǎn)出？短期均衡產(chǎn)出？uWe can see how a fall in AD can lead to a recession 總需求的降低造成經(jīng)濟衰退總需求的降低造成經(jīng)濟衰退 32清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 32未經(jīng)許可請勿翻印Fig. 13.4A Decline in Spending Leads to

21、a Recession 33清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 33未經(jīng)許可請勿翻印The MultiplieruIncome-expenditure multiplier 所得支出乘數(shù)所得支出乘數(shù)uThe effect of a one-unit increase in autonomous aggregate demand on short-run equilibrium output 一單位自發(fā)性總合需求的增加，一單位自發(fā)性總合需求的增加， 對短期均衡產(chǎn)出的影響。對短期均衡產(chǎn)出的影響。 34清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 34未經(jīng)許可請勿翻印The Multiplieru

22、Income-expenditure multiplieruAn initial change in spending uleads to a larger change in short-run equilibrium outputuSimplified form:MPCAY11dd 35清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 35未經(jīng)許可請勿翻印小組討論：P684習題5u產(chǎn)出缺口？產(chǎn)出缺口？u乘數(shù)？乘數(shù)？ 36清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 36未經(jīng)許可請勿翻印小組討論：P685習題6u產(chǎn)出缺口？產(chǎn)出缺口？u乘數(shù)？乘數(shù)？u自發(fā)性總合需求要增加多少，自發(fā)性總合需求要增加多少， 才

23、能消除產(chǎn)出缺口？才能消除產(chǎn)出缺口？ 37清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 37未經(jīng)許可請勿翻印小組討論：P685習題7u將習題將習題6中的中的NX改為改為0時，時， 短期均衡產(chǎn)出？短期均衡產(chǎn)出？u國外經(jīng)濟復甦，國外經(jīng)濟復甦，NX100時，時， 短期均衡產(chǎn)出？短期均衡產(chǎn)出？u國外經(jīng)濟衰退，國外經(jīng)濟衰退，NX-100時，時， 短期均衡產(chǎn)出？短期均衡產(chǎn)出？u經(jīng)濟景氣是否會在國際間擴散？經(jīng)濟景氣是否會在國際間擴散？ 38清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 38未經(jīng)許可請勿翻印StabilizationuThe Keynesian model says that recessions ar

24、e caused by insufficient aggregate spending 凱因素模型認為景氣衰退的凱因素模型認為景氣衰退的 主因是總合支出不足主因是總合支出不足uImplying that policymakers must find ways to increase aggregate demand 這意指決策者應(yīng)找出增加總合需求的方法這意指決策者應(yīng)找出增加總合需求的方法 39清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 39未經(jīng)許可請勿翻印StabilizationuStabilization policies 穩(wěn)定政策穩(wěn)定政策uGovernment policies that

25、are used to affect aggregate demand, with the objective of eliminating output gaps政府應(yīng)藉由政策來影響總合需求，以消除產(chǎn)出缺口政府應(yīng)藉由政策來影響總合需求，以消除產(chǎn)出缺口uMonetary policy 貨幣政策貨幣政策uFiscal policy 財政政策財政政策 40清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 40未經(jīng)許可請勿翻印Government PolicyuMonetary policyuDecisions on the size of the money supply 影響貨幣供給規(guī)模的決策影響貨幣供

26、給規(guī)模的決策uFiscal policyuDecisions about the governments budget 影響政府預算的決策影響政府預算的決策uGovernment spending 政府支出政府支出uGovernment revenues 政府收入政府收入 41清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 41未經(jīng)許可請勿翻印Government Purchases and ADuKeynes thought that changes in G would be the most effective tool for reducing output gaps 凱因斯認為調(diào)整凱因斯認

27、為調(diào)整G 是減少是減少 產(chǎn)出缺口的最佳工具產(chǎn)出缺口的最佳工具uIncreased government purchases can eliminate a recessionary gap 有衰退缺口時增加有衰退缺口時增加G 42清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 42未經(jīng)許可請勿翻印Fig. 13.5An Increase in Government Purchases Eliminates a Recessionary Gap 43清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 43未經(jīng)許可請勿翻印Fig. 13.6U.S. Military Expenditures as a Share

28、 of GDP, 1940-1999 44清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 44未經(jīng)許可請勿翻印Taxes, Transfers and ADuFiscal Policy uTax collections 租稅收入租稅收入uPayments from the private sector to the governmentuTransfer payments 移轉(zhuǎn)支出移轉(zhuǎn)支出uPayments from the government to the private sector (e.g., welfare, social security payments) 45清雲(yún)科技大學國際企業(yè)經(jīng)

29、營系CH 25 - 45未經(jīng)許可請勿翻印Taxes, Transfers, and ADuUsing taxes and/or transfers affects AD indirectly by changing disposable income 租稅與移轉(zhuǎn)租稅與移轉(zhuǎn)可支配所得可支配所得總合需求總合需求uIncrease in disposable incomeuDecrease taxesuIncrease transfersuDecrease in disposable incomeuIncrease taxesuDecrease transfers 46清雲(yún)科技大學國際企業(yè)經(jīng)營系CH

30、 25 - 46未經(jīng)許可請勿翻印小組討論：P686習題9u短期均衡產(chǎn)出？短期均衡產(chǎn)出？u當潛在產(chǎn)出等於當潛在產(chǎn)出等於580時，產(chǎn)出缺口？時，產(chǎn)出缺口？u政府支出應(yīng)改變多少才能消除產(chǎn)出缺口？政府支出應(yīng)改變多少才能消除產(chǎn)出缺口？u租稅應(yīng)改變多少才能消除產(chǎn)出缺口？租稅應(yīng)改變多少才能消除產(chǎn)出缺口？ 47清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 47未經(jīng)許可請勿翻印小組討論：P686習題9u當潛在產(chǎn)出等於當潛在產(chǎn)出等於630時，產(chǎn)出缺口？時，產(chǎn)出缺口？u政府支出應(yīng)改變多少才能消除產(chǎn)出缺口？政府支出應(yīng)改變多少才能消除產(chǎn)出缺口？u租稅應(yīng)改變多少才能消除產(chǎn)出缺口？租稅應(yīng)改變多少才能消除產(chǎn)出缺口？ 48清雲(yún)科技

31、大學國際企業(yè)經(jīng)營系CH 25 - 48未經(jīng)許可請勿翻印Qualifications of Fiscal PolicyuThe real world is more complicated than the basic Keynesian model 49清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 49未經(jīng)許可請勿翻印Qualifications of Fiscal Policyu Fiscal policy may affect potential output Y* as well as AD 財政政策不僅影響總合需求，也可財政政策不僅影響總合需求，也可能影響潛在的產(chǎn)出水準（供給面）能影響潛在

32、的產(chǎn)出水準（供給面） 50清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 50未經(jīng)許可請勿翻印Qualifications of Fiscal PolicyuInvestments in public capital increase growth and potential output Y* 公共資本投資促進成長與增加潛在產(chǎn)出公共資本投資促進成長與增加潛在產(chǎn)出uRoads, airports, schools, etc.uTaxes and transfers affect incentives 租稅與移轉(zhuǎn)影響儲蓄與投資意願租稅與移轉(zhuǎn)影響儲蓄與投資意願uPeople save less with

33、 higher taxes on savinguTax break on new investment encourages firms to make more investment 51清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 51未經(jīng)許可請勿翻印Qualifications of Fiscal Policyu供給學派強調(diào)財政政策對潛在產(chǎn)出的影響，供給學派強調(diào)財政政策對潛在產(chǎn)出的影響，在雷根擔任總統(tǒng)時（在雷根擔任總統(tǒng)時（19811985） 根據(jù)其建議，採取大規(guī)模減稅來提振景氣。根據(jù)其建議，採取大規(guī)模減稅來提振景氣。 52清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 52未經(jīng)許可請勿翻印Qual

34、ifications of Fiscal Policyu建議：建議： Policymakers should take both the demand side and supply side effects into account 決策者應(yīng)同時考慮決策者應(yīng)同時考慮 需求面與供給面需求面與供給面 53清雲(yún)科技大學國際企業(yè)經(jīng)營系CH 25 - 53未經(jīng)許可請勿翻印Qualifications of Fiscal PolicyuFiscal policy is not always flexible enough to be useful for stabilization 財政政策有時並沒有足夠的彈性財政政策有時並沒有足夠的彈性 去有效