The New Classical Macroeconomics and Stabilization Policy

MacroeconomicsPart I IntroductionChapter 1 The Science of Macroeconomics【Mainpoints】1.Exogenous Variables and Endogenous VariablesExample: The total quantity and price level of pizza in a country.Exogenous variables are given in a model. [aggregate income, price of materials]Endogenous variables are what a model explains. [price level and total quantity of pizza]2.Flexible Price and Sticky PriceFlexible price: easy to adjust, in short run.Sticky price: hard to adjust, in long run.Chapter 2 The Data of Macroeconomics【Mainpoints】1.GDP(1) Real GDP and Nominal GDP, GDP deflator(2) economy's income = economy's expenditure(3) GDP = C + G + I + NX2.CPI(1) CPI measures the price of a basket of goods(2) CPI = ∑P m Q / ∑P n Q(3) difference between GDP deflator and CPI3. The Unemployment Rate(1) Labour Force = Number of Unemployment + Number of Employment(2) Unemployment Rate = Number of Unemployment / Labour Force × 100%Part II Classical Theory: The Economy in the Long Run ---- Flexible Price Chapter 3 National Income: Where It Comes From and Where It Goes【Mainpoints】1.Total Production(1) Production Function: Y = F(L,K)(2) constant returns to scale: zY = zF(L,K)2. National Income Distribution(1) Factor Prices ---- Labour:MPL = F(L+1,K) - F(L,K)ΔProfit = ΔRevenue - ΔCost = MPL×P - WIn order to maximize profit, make ΔProfit = 0. So MPL=W/P, Real WageLabour Income = MPL×L(2) Factor Prices ---- CapitalMPK = F(L,K+1) - F(L,K)ΔProfit = ΔRevenue - ΔCost = MPK×P - RIn ordet to maximize profit, make ΔProfit= 0 . So MPK=R/P, Real Rental Price of CapitalCapital Income = MPK×K3)The Cobb-Douglas Production FunctionLabour Income = MPL×L = (1-α)YCapital Income = MPK×K = αY→F(K,L) = AKαL(1-α) , A measures the productivity of the available technology3.Total Demand1)Consumption:Determined by disposable incomeC=C(Y-T)Marginal Propensity to ConsumeMPC=C(Y-T+1)-C(Y-T)2)Investment:Determined by interest rateI=I(r)When r is high, investors will give upinvestment because cost of loan is higherthan rate of return.3) Government PurchasesG vs T, measures government budget5. Equilibrium (in a closed economy)(1) Market of Goods and ServicesY=C(Y-T)+I(r)+G(2) Market of Loanable FundsS=Y-C(Y-T) - G = I(r)investment is crowded out Chapter 4 Money and Inflation【Mainpoints】1.Concept of Money(1) Funtions of Money: 1) Store of Value. Example: You can hold your money and trade itfor goods and services at some time in the future.2) Unit of Account. Example: In store people use money to showprice.3) Medium of Exchage. Example: People use money as tool toexchange goods.(2) Types of Money: 1) Fiat Money. No value, example: Paper Money.2) Commodity Money. With value, example: Gold and Silver.(3) Control of Money: 1) Institution: Central Bank. Example: Deutsche Bundesbank2) Method: Open-Markt Operation. Example: Buy governmentbonds to increase money supply.2.The Quantity Theory of Money(1) Quantity Equation: MV=PT →MV=PYQuantity Theory of Money: MV=PY(2) Real Money Balances: M/P , measured in quantity of goods and services.The Money Demand Function: (M/P)d = L(Y,i) = M/P← Money Supply. Y↑, d↑; i↑,d↓(3) Money and Inflation: ΔM% + ΔV% = ΔP% + ΔY% So M↑, P↑3.Inflation and Interest Rate(1) Fisher Equation: i = r + πChapter 5 The Open Economy【Mainpoints】1.International Trade in a Samll Open Economy(1) View of goods and capital flow: NX = Y- (C+G+I)(2) View of capital flow: NX = Y-C-G-I = S-I= S-I(r*)r* is World Interes Rate(3) Trade Policies: 1) Domestic Fiscal Policy, influenceG↑,T↓→S↓→NX↓2) Fiscal Policy Abroad, influenceG e↑, T e↓→S e↓→r*↑→NX↑3) Shift in investment demand. Example: Government provides aninvestment tax credit2.Exchange Rates(1) Nominal Exchange Rates(e) and Real Exchange Rates(ε)Nominal exchange rates are measured in currency. Example: 100 yen / 1 dollarReal exchage rates are measured in goods and services. Example: 2 Japan Car / 1 USA car ε = e × (P/P*) , P* means price level of foreign countries.(2) The Real Exchange Rates and Trade Balance:NX = NX(ε)ε↓, P/P*↓, mean s domestic goods and servicesare cheaper than abroad. NX↑When NX(ε) = S - I, ε is equilibrium real ex.rate.(3) Trade Policies: 1) Domestic Fiscal Policy:G↑,T↓ → S↓(Expansionary Fiscal Policy)2) Fiscal Policy Abroad:G e↑, T e↓→S e↓→r*↑→I↓3) Shift in investment demand.4) Shift in NX(ε) Example: Protectionist Trade Policies(4) Inflation and nominal exchange rates:e = ε × (P*/P) → Δe%= Δε% + (π* - π)(5) PPP(Purchasing-Power Parity): 1 Dollar can buy the same quantity of wheat in anycountry.Chapter 6 Unemployment【Mainpoints】1.Natual Rate of Unemployment(1) Concept: The rate of unemployment which the economy get closed to in the long run.(2) Calculation: L-Labour Froce, E-Number of Employed, U-Number of Unemployed, f-rate of job fiding, s-rate of job seperating.L=E+U, fU=sE → U/L=1/(1+f/s)2.Causes for Unemployment(1) Frictional Unemployment:Unemployed people need time to find jobs.e.g. sectoral shift, unemploymetn insurance.(2) Structural Unemployment:Wage Rigidity. Wage is above the equlibrium level.e.g. Minimum-Wage Laws, Unions, Efficiency Wages.Part III Growth Theory: The Economy in the Very Long Run ---- Solow Growth Model Chapter 7 Economic Growth I: Capital Accumulation and Population GrowthAssumption: Constant Return to Scale【Mainpoints】1.Capital Accumulation(1) Production Function per worker: zY=F(zK,zL)→Y/L=F(K/L,1)→y=f(k),MPK=f(k+1)-f(k)(2) Output and consumption per worker: y=c+i→c=(1-s)y→i=sy→i=sf(k)(3) The Steady State: Capital stock growth Δk = 0Δk=i-δk, δ is depreciation rate→Δk=sf(k)-δk=0→sf(k*)=δk*(4)Golden Rule level of capital: k*gold which maximizes cc=y-i→c=f(k)-sf(k)→c*=f(k*)-δk*→c max:MPK=δ2. Population Growth(at rate of n)(1) The Steady State:Δk=i-k(δ+n)→Δk=sf(k)-k(δ+n)=0→sf(k*)=(δ+n)k*(2) Golden Rule level of capital:k*gold, c=y-i→c max:MPK=δ+nChapter 8 Economic Growth I: Technology, Empirics, and Policy1.Technological Progress in the Solow ModelAssumption: Technology growth is a given exogenous variable g(1) Efficiency of Labour: Y=F(K,EL)(2) The Steady State: Δk=sf(k)-(g+n+δ)k=0→sf(k*)=(g+n+δ)k*(3) Golden Rule level of capital: k*gold , c=y-i→MPK=g+n+δ2.Endogenous Growth TheoryAssupmtion: Technolgy growth is a endogenous function g(μ), capital includes knowledge (1) 2 Sector Model: Y=F[K,(1-μ)EL], ΔE=g(μ)E, ΔK=sY-δKPart IV Business Cycle Theory: The Economy in the Short Run ---- Sticky Price Chapter 9 Introduction to Economic Fluctuations【Key Concepts】Recession: A period of falling output and rising unemployment.Business Cycle: Short-run fluctuations in output and employment.【Mainpoints】1.GDP and unemployment(1) Okun's Law: ΔReal GDP%=3%-2×ΔUnemployment Rate(2) Leading Economic Indicators: Forecasts. Example: Average work time, Index of stock prices, Money Supply....2.Aggregate Demand and Aggregate Supply( P=P(Y))(1) The Quantity Theory of Money→AD: MV=PY→M/P=(M/P)d=kY(2) AS: SRAS---P=P, LRAS---Y=Y(3) From Short Run to Long Run: M changes AD, Y is unchanged inthe long run, but P in the long run changes. (A→B→C)(4) Shocks to AD and AP:1) Shocks to AD. Example: Credit Card makes V rise.Policy: Reduce the Money Supply.2) Shocks to AP. Example: A drought that destroys crops. Cartel. Union. etc. P↑Policy: Wait! Then price returns original level eventually(But it takes longtime). Or expand AD(But price level will be high in long period of time) Chapter 10 Aggregate Demand I: Building the IS-LM Model (Y-r)【Mainpoints】1.IS Curve(1) Good and Service Market→The Keynesian Cross: Y=C+I+G, PE=AE(2) IS curve:Y=C(Y-T)+I(r)+G 1) r↑→I↓→Y↓ 2) Fiscal Policy: G↑→Y↑→IS→, Governmetn-purchases multiplier, tax multiplier.2.LM Curve(1) Money Market→The Theory of Liquidity Peference: M/ P=L(r), M s=M d(2) LM Curve: M/P=L(r,Y). 1) Y↑,M d↑,r↑ 2)M s↑,r↓,LM←3. The Short-Run EquilibriumChapter 11 Aggregate Demand II: Applying the IS-LM Model (Y-P)【Mainpoints】1.IS-LM Model as a Theroy of Aggregate Demand(1) Derivation: P↑,(M/P)s↓,r↑,LM↑→Y↓(2) Shift in AD: G,T,M→IS/LM→Y(3) In long run and short run: In long run Y<YChapter 12 The Open Economy Revisited: The Mundell-Fleming Model and the Exchange Rate Regime【Mainpoints】1.Mundell-Fleming Model(1) IS* Curve: Y=C(Y-T)+I(r*)+G+NX(ε) (2) LM* Curve: M/P=L(r*,Y)2.Under Floating Exchange Rates(1)Fiscal Policy:Shift IS*,ineffectual; Monetary Policy:Shift LM*; Trade Policy:Shift NX(ε)→IS* 3.Under Fixed Exchange Rates(1) Theory: Arbitrageur arbitrage so that M changes.(2)Fiscal Policy shifts IS*→LM*; Monetary Policy:Shift LM*, ineffectual; Trade Policy: Shift NX(ε)→IS*→LM*4. Policy Choice: Impossible Trinity5. Mundell-Fleming Model in Short andLong RunChapter 13 AS and the Short-Run Tradeoff Between Inflation and Unemployment1.Aggregate Supply ModelY=Y+α(P-P e)2.Inflation, Unemployment and Phillips Curve(1)Y=Y+α(P-P e)→P-P-1=P e-P-1+1/α(Y-Y)+v→π=πe+β(μ-μn)+v [Okun's Law] v-supply shock(2) Sacrifice Ratio: π↓1%, GDP ↓ ? %Part V Macroeconomic Policy DebateChapter 14 Stabilization Policy1.Inside Lag and Outside Lag(1) Inside lag is the time between economy shock and the policy anction responds. Example: Policy makers need time to recognize a shock and react.(2) Outside lag is the time between a policy action and its influence on the economy. Example: Change in money supply and interest rate.Chapter 15 Government Debt and Budget Deficits1.The Traditional View of Government Debt(1) In the short run, T↓,C↑,S↓,r↑,I↓,lower steady-state K and a lower level of Y.(2) In the lo ng run, T↓,C↑,IS→,AD↑, finally Y=Y, P i s higher.(3) In open economy, T↓,C↑,IS→, ε↑2.The Ricardian View of Government Debt(1) Ricardian Equivalence: Consumers are forward-looking.They think that government will raise tax at some point in the future, in order to afford budget. So they won't change consumption.Part VI More on the Microeconomics Behind MacroeconomicsChapter 18 Money Supply, Money Demand and the Banking System1.Money Supply(1) Money Supply (M) = Currency (C) + Demand Deposits (D)(2) Reserves: The money that bank receive but don't lend out. Reserve-deposit ratio-rr1) 100% Reserve Banking. 1C→1D, M remains constant.2) Fractional-Reserve Banking. 1C→rrD+(1-rr)C, M increases. And (1-rr)C can be put into another bank, the process of money creation can be continued.(3) Money Supply Model: M=C+D.B(Monetary Base)=C+R [Control by Central Bank]→ M=(cr+1)/(cr+rr)×B=m×B [cr is currency-deposit ratio](4) Monetary Policy Tool: open-market operation, reserve requirements, discout rate[the rate that banks borrow from central bank].2.Money Demand(1) Quantity Theory: (M/P)d=L(i;Y)(2) Portfolio Theory: (M/P)d=L(r s,r b,πe,W) [r s-expected real return on stock, r b-expected real return on bonds, W-real wealth]。

新凯恩斯主义形成的历史背景为答复本世纪70年代所谓“凯恩斯主义理论危机”，80年代便产生了新凯恩斯主义经济学。

70年代兴起的新古典宏观经济学的学者们认为，凯恩斯主义经济学在理论上是不恰当的，他们断言，宏观经济学必须建立在厂商微观经济的基础上；他们主张，应当用建立在市场始终出清和经济行为者始终实现最优化的假定基础之上的宏观经济理论来取代凯恩斯主义经济学。

早在70年代后期，斯坦利·费希尔（Stanley Fischer）、埃德蒙·费尔普斯（Edmund Phelps）、约翰·泰勒（John T aylor）就为新凯恩斯主义经济学建立基础。

费希尔发表了《长期合同、理性预期和最佳货币供应规则》一文（载《政治经济学杂志》1977年2月号），费尔普斯和泰勒发表了《在理性预期下货币政策的稳定性力量》一文（载《政治经济学杂志》1977年2月号）。

他们吸收了理性预期假设。

80年代，美国一批中青年经济学者致力于为凯恩斯主义经济学主要组成部分提供严密的微观经济基础。

因为工资和价格粘性往往被视为凯恩斯主义经济学的主题，所以他们努力的目的在于更多表明这些粘性如何由工资和价格确定的微观经济学而引起的。

即是，他们试图建立工资和价格粘性的微观经济基础。

这样，80年代以来，就形成新凯恩斯主义经济学（New—Keynesian Economics），以与其对立的研究方法，即新古典宏观经济学（New—Classical Macroeconomics）相并立。

事实上，以萨缪尔森为首的新古典综合派亦称为新凯恩斯主义，它以“new”表明“新”的意义，因此，是对旧凯恩斯宏观经济学和古典微观经济学的“新古典综合”（neoclassical synthesis），现在，标名“新凯恩斯主义的”，英文原文为“new—Keynesian”，此词是迈克尔·帕金（Michael Parkin）所创造的，他于1984年出版的《宏观经济学》一书，始创“新凯恩斯理论”（new—Keynesian theory ）这个术语，而未用“新凯斯主义宏观经济学”。

2021凯恩斯不同阶段宏观经济理论的价值分析范文 摘要:在宏观经济学的发展历程中,凯恩斯主义始终占据着重要位置.通过严厉批判传统古典经济理论中的市场完美假说以及"萨伊定律",凯恩斯主义经济学强调了政府干预对稳定经济的重要性.凯恩斯主义宏观经济学一直处于动态发展之中,先后经历了萌芽、《通论》出版、正统凯恩斯主义、后凯恩斯主义、第一代新凯恩斯主义和第二代凯恩斯主义等发展阶段,每个阶段的凯恩斯主义模型都具有丰富的理论价值和现实意义.鉴于此,本文系统归纳了凯恩斯主义宏观经济理论的历史发展脉络,分析了每个阶段凯恩斯主义的理论基础和核心特征. 关键词:凯恩斯主义;市场失灵; 政府干预; 作者简介: 郭佩颖,男,博士,中国人民银行长春中心支行,经济师.; Abstract:Inthe development of macroeconomics,Keynesianism has always occupied an important position.By sternly criticizing the market perfection hypothesis and the "Say's Law" in traditional classical economictheory,Keynesian economics has emphasized the importance role of government intervention to stabilize the economy.Keynesian macroeconomics has been in a dynamic development,It has undergone successive stages ofdevelopment,such as the germination,the publication of General Theory,the orthodox Keynesianism,post-Keynesianism,the first generation of New Keynesianism,and the second generation of Keynesianism.The macro model of each stage has rich theoretical value and practical significance.In view of this,this article systematically summarizes the historical development context of Keynesian macroeconomic theory,and analyzes the theoretical basis and core characteristics of Keynesianism at each stage. Keyword:keynesianism;market failure; government intervention; 1936年,凯恩斯出版了经济学巨着《就业、利息和货币通论》(Keynes,1936),书中率先将宏观经济变量的行为、表现及结构特征整合到一起,试图从总量层面系统阐释经济短期大幅波动的潜在原因及应对举措,Blanchard(2000)认为,凯恩斯是第一个将研究宏观经济现象所需的实际变量和货币变量整合到一个单一正式框架的人.这种将总体经济整合到一起进行系统论述的研究范式标志着现代宏观经济学的诞生.至此以后,宏观经济学得到了持续快速的发展,演化出几个关键的理论发展阶段.在每个阶段,不同学派相互辩争,构建出大量卓有见识的经济模型,显着提升了宏观经济理论的现实解释力. 在滞涨等历史时期,凯恩斯主义宏观经济理论推崇的政府干预思想被认为是导致经济衰退的罪魁祸首.诸如奥地利学派、货币学派和新古典学派等宏观经济理论都试图将凯恩斯主义击碎驳倒,在其后的较长时期里,凯恩斯主义思想陷入了发展低迷期,但在吸纳其他理论模型的优点后,凯恩斯主义宏观模型逐渐焕发了生命力,尤其在应用层面,凯恩斯主义思想对政府实行逆周期调节也发挥了更为重要的影响力.基于此,本文系统探析了凯恩斯主义宏观经济理论的总体发展脉络,重点分析每个发展阶段中凯恩斯主义宏观经济理论取得的重要成就及核心特征. 一、凯恩斯主义的萌芽 经济形势的突变往往为新理论的诞生演化提供了重要动力.Gordon(2000)认为,历史事件的发展常常使得某种主流理论面临挑战并最终被驳倒,从而促生出更具解释力的新理论.1929年美国股市暴跌引发的全球经济大萧条便是符合这样特征的重大历史事件,大萧条初期的主流应对方案来自传统经济理论,其中,古典经济理论认为市场能够自发实现帕累托最优,经济衰退只是市场出清过剩产能的阶段性现象,对于大萧条,自由放任的市场调节就是最好的应对举措.当时,具有重要影响力的奥地利学派也持类似看法,该学派认为大萧条源自过度投资和资源错配,要积极应对经济危机,就必须让市场自发实行一系列"清算",如劳动力实际报酬降低的同时任由过度投资企业破产倒闭. 然而,随着实际工资降低和企业退出市场等清算举措的实行,欧美市场并没有实现传统古典理论所预计的复苏,相反经济衰退程度不断加重,大萧条的负面影响大幅蔓延,最严重时期美国工业产出下降46.8%,GDP下降28%,失业率为25%(Romer,2004).这种经济活动的灾难性下降是空前的,经济理论界开始质疑传统经济理论所倡导的自由放任原则,并思考市场自发调节的局限性以及政府应对市场失灵的积极作用.在理论急需革新的关键时刻,凯恩斯宏观经济理论应运而生.凯恩斯认为,大萧条时期经济频繁的剧烈波动严重恶化了经济体系的健康运行,以相对价格运行为核心的市场自发调节机制并不能有效熨平经济剧烈波动,面对市场失灵,政府在投资层面应该发挥更多重要作用.Deutscher(1990)的研究数据表明,在《通论》出版以后,凯恩斯主义已在当时的宏观经济学中处于主导地位.Samuelson(1988)认为,凯恩斯革命是20世纪经济学最重大的事件. 二、《通论》涉及的几个主要理论 为了系统阐述自己的观点,凯恩斯写作了《就业、利息与货币通论》,本书出版后,迅速被经济学界奉为圭臬,Tobin(Snowdonand Vane,2005)强调,这一新兴理论使他们那一代人面临的诸多问题得到了建设性的解决.随即,凯恩斯主义宏观经济理论发展迅猛,成为主流宏观经济理论.凯恩斯在《通论》中力图阐述的几个主要观点得到学术界的普遍关注,已成为凯恩斯宏观经济学的理论基石,大致可以总结如下. (一)有效需求理论 有效需求是指总需求与总供给相等时的均衡需求.凯恩斯认为,受边际消费倾向递减、资本边际效率递减以及灵活偏好规律等三大规律的影响,消费者常常会将收入更多用于储蓄,消费占比会系统性偏低,有效需求自然会出现不足倾向,即社会总供给并不能被总需求完全消化掉,社会各类商品滞销,存货增加,产能过剩迫使生产缩减,企业解雇工人,失业率增加. (二)非自愿失业理论 大萧条时期,大量工人失去工作,凯恩斯试图对这种现象给予经济学解释.他将失业分为摩擦性失业和非自愿失业,前者被认为是市场自发调节状态下的季节性和技术性失业,属于在所难免的正常状态;后者属于市场失灵后剧烈波动所引发的畸形反常情况.非自愿失业状态下,即使求职人员要求的工资低于市场工资水平,但仍难以寻觅到工作.显然,凯恩斯并不认为劳动力市场总能处于供求均衡的市场出清状态,当价格刚性条件下,名义工资弹性不充分,不能产生足够的力量使得劳动力市场恢复到充分就业的状态,非自愿失业就成为劳动力市场的一个常态特征. (三)政府干预理论 凯恩斯认为,供给创造需求的萨伊定律面临短期局限,市场自发调节在短期内并不能一直使得资源得到优化配置,总供给高于总需求的市场格局难以自动调节出清.为了解决这种缺陷,凯恩斯认为政府这只"看得见的手"也应该积极发挥作用,政府可以采用扩张性政策来增加公共支出,以公共部门支出的增量来弥补私人部门支出的减量,填补有效需求不足的缺口,从而促使宏观经济实现平稳持续增长. 三、正统凯恩斯学派 学界普遍认为《通论》是一本兼具复杂性和争议性的巨着.Patinkin(1990)认为,凯恩斯并未构建出一个明确完整的模型来统一分析主要宏观经济问题.相反,《通论》有的地方论述较为模糊,前后观点甚至相互矛盾,这就促生了大量试图解读本书核心内容的作品,从目前来看,多种解读仍未形成一个系统的学术共识,甚至观点相左的经济学家都认为自己的理论承袭于凯恩斯思想.但值得注意的是,在20世纪50年代至70年代的近二十年间,希克斯、莫迪尼阿尼和汉森等学者所开创的以IS-LM模型为核心的正统凯恩斯学派产生了巨大影响力,主导了当时宏观经济学的发展,其理论价值直到今天仍值得重视. (一)IS-LM模型 正统凯恩斯学派最早起源于希克斯的着名论文《凯恩斯先生与古典经济学》(Hicks,1937),希克斯重新整理了凯恩斯思想的主要理论,归纳出了产品市场和货币市场的均衡状态,即IS-LM模型,随后莫迪尼阿尼和汉森分别对其做了进一步拓展.实际上,IS-LM模型从出现以后就成为宏观经济学的重要模型,对当时各国宏观经济政策的制定产生了重要影响(DeVroey,2016). 如图1,IS曲线表示的是产品市场均衡状态下利率与收入的关系轨迹,根据IS曲线的走势可以看出,收入与利率呈负相关关系,当利率偏低时,投资会增加,收入也会随之提升.LM曲线表示货币市场均衡时利率与收入的关系轨迹,货币市场中,收入的提升会增加投资性货币的需求,货币供给保持不变时,货币需求增加会提升利率水平,即货币市场收入与利率呈现正向关系,LM曲线向上倾斜.显然,IS-LM模型具有重要的政策含义,财政政策会影响产品市场,使得IS曲线平移;货币政策会影响货币市场,使得LM曲线平移.不同政策导致曲线平移后新的交点就是产品市场和货币市场新的平衡点,对比之前的均衡水平,就可以看出收入和福利的改变情况. (二)Klein宏观计量经济模型 在研究《通论》时,Klein意识到凯恩斯的诸多宏观判断缺乏计量实证的支持,为了填补实证研究的空缺,Klein基于凯恩斯理论构建了大量的计量实证模型,开创了宏观计量经济模型研究的新领域. 在IS-LM模型的基础上,Klein和Goldberger(1955)构建了一个包含15个结构方程和5个恒等式的计量经济模型来刻画美国经济.该模型试图评估各类政策工具的运用效果,同时试图预测经济活动走势.显然,Klein宏观计量模型充分验证了凯恩斯经济理论对经济现实的解释力,加入价格和工资调节机制以后,该模型理清了劳动力市场的运行机制,实证支持了凯恩斯非自愿失业等理论判断. (三)菲利普斯曲线 菲利普斯曲线描述了就业与通胀之间的相关轨迹,最早是由伦敦政治经济学院教授菲利普斯在估算1861-1957年间英国工资与失业之间的关系时发现的(Phillips,1958).菲利普斯的研究成果基本上属于统计经验性的,当时欧美国家劳动力市场普遍符合其规律,即失业与工资之间呈现负相关关系,只要就业市场趋紧,失业就会下降,工资便会上升;而在就业市场宽松时,失业和工资便会呈相反变动规律,有力证实了菲利普斯曲线. 在此基础上,Samuelson和Solow(1960)进一步发展了该理论,他们将工资扩展为一般物价,将菲利普斯曲线转化为就业与物价之间的负相关关系.当时,宏观经济学界以正统凯恩斯主义经济学为核心,菲利普斯曲线自然很快成为凯恩斯主义的核心理论,正统凯恩斯经济学认为:物价与就业之间的负相关关系为政府制定政策提供了完美的理论框架,当政府想降低就业时,只需放宽货币政策,制造适应的通胀即可.随后,菲利普斯曲线成为政府制定就业政策的重要理论依据,深刻影响了当时的政策走势. 四、新凯恩斯宏观经济理论 随着凯恩斯经济学的广泛影响,欧美国家普遍接受了政府积极干预的思想,干预色彩蔓延到市场体系的各个角落,国有企业数量占比处于较高水平,公共部门规模不断扩大.随着政府财政负担的攀升以及经济效率的下降,20世纪70年代至80年代,欧美国家普遍发生了高通胀、高失业与低增长并存的滞涨现象,对政府干预过多的批评逐步成为主流,推崇市场自发调节的古典思想开始复兴.以卢卡斯为代表的新古典经济学对正统凯恩斯经济理论提出了严厉批评,该学派认为,政府也会犯错,试图平滑经济波动的财经政策可能会起到相反作用,进一步加剧经济波动,对此,政府应该发挥有限的公共作用,不断从市场体系中推出,市场自发调节就可以促使宏观经济平稳发展.针对计量实证方法,Lucas和Sargent(1981)批评道,考虑理性预期以后,凯恩斯主义使用的计量模型是存在严重不足的,模型参数会随着宏观环境变化而变化,根据以往时间序列估算出来的模型参数存在明显的结构缺陷,因此不能准确预测经济走势. 为了弥补凯恩斯经济学的理论缺陷并增强现实解释力,新一批凯恩斯主义经济学家做了大量的开创性研究,在吸收新古典经济学方法论的基础上,共同构建了新凯恩斯宏观经济理论.新凯恩斯主义一方面继承了传统凯恩斯理论中非自愿失业、价格刚性和货币非中性等市场非完全性概念,正如Stigliz(2000)所说,新凯恩斯主义方法的精髓在于将现实世界中的诸多不完美引入到经济学理论模型中.另一方面新凯恩斯理论又积极借鉴了新古典经济理论的基础方法,将微观基础和一般均衡作为建模的根本原则,从而填补了凯恩斯主义在供给方面所存在的理论空白. 一般而言,新凯恩斯宏观经济理论主要具有以下特征:一是具有微观基础的价格刚性.新凯恩斯经济学家利用菜单成本或效率工资等理论模型将微观基础和价格刚性整合到一起.该类模型认为,即使价格调整的成本很小时,价格刚性仍然会存在,这种看似微小的刚性会带来显着的宏观经济影响.二是否定古典二分法,坚持货币非中性.Mankiw和Romer(1991)认为,由于价格刚性的存在,名义变量的波动会带来实际产出效应,货币供给量的增加不是引起物价的普遍上涨,而是引起某些产出增长更快,即货币非中性引起产出出现结构性增长.三是市场失灵是解释经济周期波动的关键因素.新凯恩斯主义认为,市场普遍存在垄断竞争、异质劳动力结构、信息不对称以及外部性等特征,当供给或需求产生外生冲击后,市场失灵会放大这些冲击,导致产出和就业出现大幅波动.四是非自愿失业存在的合理性.新凯恩斯主义中例如效率工资等模型都清楚证明了非自愿失业的存在,这类模型认为,设定高于供求均衡的效率工资是为了激励工人的工作积极性,但同时也会增加企业生产成本.为了减少生产成本,企业会缩减雇佣员工数,导致市场均衡时自然出现非自愿失业(Akerlof and Yellen,1986). 五、第二代新凯恩斯宏观经济理论 古典二分法是否成立,即货币是否具有实际影响,成为凯恩斯主义和古典主义的根本分水岭.大萧条以后,凯恩斯货币理论占据了学术高位,随后,弗里德曼与卢卡斯复兴了货币中性理论,而第二代新凯恩斯宏观经济理论则在新的理论基础上再次复兴了凯恩斯的货币理论.相比于重点论述价格刚性、非自愿失业、市场非出清的第一代新凯恩斯主义,第二代新凯恩斯宏观经济理论是以动态随机一般均衡模型(DSGE)为基础,DeVroey(2016)认为,该理论重点论述最优货币政策的实施路径,即考虑名义价格刚性的前提下,以DSGE模型来讨论中央银行的政策目标及影响. 第二代新凯恩斯宏观经济理论受益于DSGE基准模型的发展,它的论证思路可以简述为在资源约束条件下求解动态最优化的欧拉方程.由于加入了垄断竞争、名义价格刚性和中央银行行为等结构变量,均衡求解会牵涉个人、企业和中央银行,模型论证变得更加复杂.大致而言,第二代新凯恩斯宏观经济理论原创性主要体现在总需求方程、新版菲利普斯曲线方程以及修订的泰勒规则方程.其中,前两个方程采用了稳态附近的对数线性化形式来表达个人和企业在决策时的最优状态,第三个方程刻画了中央银行的最优决策,中央银行通过调整实际利率促使实体经济走向最优均衡.考虑这三个方面后,中央银行如能严格遵照具体规则实施货币政策,政府按照跨期预算约束来实施财政政策,那么整体经济就可以实现帕累托最优. 六、后凯恩斯学派 凯恩斯宏观经济学还有一个重要的流派,这个学派内部汇集了大量观点迥异的经济学家,他们以反对萨缪尔森等人的新古典综合理论为共识,一般将该学派的宏观经济建模方法统称为后凯恩斯经济学.但是这些风格多样的建模思路常常来自传统古典经济学,而非源自凯恩斯《通论》中的核心理论框架,所以后凯恩斯主义经济学是一个思想庞杂的学派,为了准确界定该学派的核心特征,Davidson(2003)认为,只有采用了凯恩斯有效需求原则和流动性偏好理论的分析模型才能够算后凯恩斯主义,显然主流凯恩斯主义忽视了这两方面的重要性. 后凯恩斯主义经济学相信凯恩斯的有效需求原则能够用于准确分析宏观经济波动,它强调了需求侧对解释经济周期波动和经济运行失衡的重要性,根本否定了古典经济理论中的供给创造需求的萨伊定律.一般而言,后凯恩斯主义经济学具有以下重要特征:一是货币非中性是长久存在的,无论是在短期还是长期,货币决策都能影响实际生产.后凯恩斯主义认为,货币数量的增加能够增加经济体的结构性需求,影响生产物品的相对价格,促使生产结构性增加并提高就业.二是经济生活决策中面临非遍历的不确定性.后凯恩斯主义者认为经济行为面临的不确定性不是概率分布问题,而是随机过程理论中的非遍历随机体系.在经济行为人做出决策后,经济体系是不断变化的,不可预见的不确定性普遍存在,这种未知是无法得到准确计算和评估的.三是非自愿失业是普遍存在.后凯恩斯理论坚信一个运转良好的市场体系中仍然会存在非自愿失业,市场运行不可能消除全部失灵现象,现有问题解决后又会迸发新问题,所以失业也就成为市场运行中始终存在的经济现象. 七、结语 综上所述,凯恩斯思想的影响是深远且广泛的.随着《通论》的出版,强调市场不完全性和政府干预必要性的凯恩斯学说在宏观经济学殿堂中就一直占据着重要位置.相比于新古典学派提倡市场完美假说并强调理论模型的优美,凯恩斯宏观经济学体系更加推崇实用主义,即经济现实对构建宏观经济模型的重要性.现实经济运行存在许多不完美特征,例如非自愿失业、垄断竞争、价格刚性、外部性、货币非中性等等,这些不稳定因数会导致市场偏离均衡呈现周期波动.因此,从实践层面而言,凯恩斯主义宏观经济理论更具有应用解释价值.。

新古典宏观经济学和新凯恩斯主义经济学对政府干预经济的认识一、古典宏观经济学与凯恩斯主义经济学对政府干预的认识与新古典宏观经济学（New classical macroeconomics）和新凯恩斯主义经济学(New Keynesian economics)相对应的概念自然是古典宏观经济学与凯恩斯主义经济学。

马克思首先提出了古典政治经济学与古典经济学这个概念，指的是资本主义上升时期代表新兴资产阶级利益并研究资本主义生产关系内部联系的政治经济学或经济学。

按照马克思的规定，古典经济学家指的是配第、斯密、李嘉图等人，庸俗经济学家如马尔萨斯、萨伊、穆勒等并不被包括在内。

凯恩斯使用了古典经济学家这一术语，但是他抹杀了古典经济学与庸俗经济学的界限，又将马克思所说的古典经济学与西方经济学家所说的新古典经济学（Neoclassical economics）混同一谈。

新古典经济学指的就是边际主义经济学，代表人物有：杰文斯、门格尔、瓦尔拉斯、帕累托、克拉克、费雪、马歇尔、庇古等。

而我们现在所谓的古典宏观经济学指的就是经过系统化的新古典经济学的宏观经济理论。

认为通过工资、价格与利率自动伸缩机制可以使劳动、资本、货币与商品市场同时达到均衡。

市场经济能够自行调节，有自动走向充分就业的趋势，政府对经济的干预是不必要的，也是无效的。

凯恩斯主义经济学指的是凯恩斯的追随者所诠释与发展的凯恩斯的经济理论与政策主张。

这一派的经济学家最著名的有汉森、希克斯、克莱因、萨缪尔森和托宾等人。

古典宏观经济学不能解释上世纪30年代的大萧条。

凯恩斯主义经济学应运而生，要为经济危机的存在与政府干预的必要性提供理论基础。

凯恩斯将市场失灵归咎于价格刚性，认为它使市场力量受到阻碍，只有政府实施稳定性政策来进行调节经济。

他认为有效需求决定产出，而由于边际消费倾向递减，有效需求往往小于充分就业均衡的需求，这就要求政府干预经济，刺激有效需求，使经济达到充分就业均衡。

宏观经济学原理曼昆名词解释微观经济学（microeconomics），研究家庭和企业如何做出决策，以及它们如何在市场上相互影响。

宏观经济学（macroeconomics），研究整体经济现象，包括通货膨胀、失业和经济增长。

国内生产总值GDP（gross domestic product），在某一既定时期，一个国家内生产的所有最终物品与服务的市场价值。

消费（consumption），家庭除购买新住房之外，用于物品与服务的支出。

投资（investment），用于资本设备、存货和建筑物的支出，包括家庭用于购买新住房的支出。

政府购买（government purchase），地方、州和联邦政府用于物品与服务的支出。

净出口（net export），外国人对国内生产的物品的支出（出口），减国内居民对外国物品的支出（进口）。

名义GDP（nominal GDP），按现期价格评价的物品与服务的生产。

真实GDP（real GDP），按不变价格评价的物品与服务的生产。

（总之，名义GDP是用当年价格来评价经济中物品与服务生产的价值，真实GDP是用不变的GDP平减指数（GDP, deflator），用名义GDP与真实GDP的比率乘以100计算的物价水平衡量指标。

消费物价指数CPI（consumer price index），普通消费者所购买的物品与服务的总费用的衡量指标。

通货膨胀率（inflation rate），从前一个时期以来，物价指数变动的百分比。

生产物价指数（producer price index），企业所购买的一篮子物品运服务的费用的衡量指标。

指数化（indexation），根据法律或合同按照通货膨胀的影响，对货币数量的自动调整。

名义利率（nominal interest rate），通常公布的、未根据通货膨胀的影响，校正的利率。

真实利率（real interest rate），根据通货膨胀的影响校正过的利率。

Macroeconomics is a fundamental branch of economics that examines the overall functioning and performance of an economy on a large scale, encompassing variables such as inflation, unemployment, economic growth, and international trade. This analysis delves into several key aspects of macroeconomics, providing a multi-dimensional understanding of its core principles.**Introduction to Macroeconomic Indicators**At the heart of macroeconomics lies a set of crucial indicators that serve as barometers for the health of an economy. Gross Domestic Product (GDP) is the primary measure of an economy's total output of goods and services, offering insights into economic growth. Unemployment rate measures the percentage of the labor force without work but actively seeking employment, reflecting the efficiency of the labor market. Inflation, represented by Consumer Price Index (CPI), measures the average change over time in the prices paid by consumers for a basket of goods and services, indicating purchasing power and monetary stability.**Economic Growth and Development**Macroeconomic policies aim at fostering sustainable economic growth through increasing productivity, investment, and technological advancement. Fiscal policy, involving government spending and taxation, can stimulate or cool down the economy. For instance, during a recession, expansionary fiscal policy may be implemented through increased government expenditure or tax cuts to boost aggregate demand. Conversely, contractionary fiscal policy helps curb inflation during economic booms.Monetary policy, executed by central banks, regulates money supply and interest rates to influence economic activity. Lowering interest rates encourages borrowing and investment, which can lead to increased consumption and production; raising interest rates can reduce inflation by dampening spending and investment.**Business Cycles and Stabilization Policies**Macroeconomics also explores the phenomenon of business cycles - periodsof expansion, peak, contraction, and trough in economic activities. Economists strive to understand these fluctuations and design stabilization policies to mitigate their negative impacts. The Keynesian perspective emphasizes the role of aggregate demand in driving economic cycles, advocating for active government intervention to stabilize output and employment.On the other hand, classical and new classical economists highlight the importance of long-term structural factors and the potential limitations of short-term stabilization policies due to price flexibility and rational expectations.**International Trade and Exchange Rates**Globalization has made international trade and capital flows integral components of modern macroeconomics. The balance of payments records all transactions between a country and the rest of the world, including exports, imports, and financial investments. Exchange rates, determined by the forces of supply and demand for currencies in foreign exchange markets, affect international competitiveness, inflation, and the overall balance of payments.Moreover, the Mundell-Fleming model, an extension of the IS-LM model, shows how monetary and fiscal policies interact with exchange rates in open economies, underlining the complexities involved in managing national economies amidst global interconnectedness.**Conclusion: Challenges and Future Directions**In conclusion, while macroeconomics provides essential tools to understand and manage national economies, it faces numerous challenges. These include addressing income inequality, ensuring environmental sustainability, and dealing with global imbalances. Future directions in macroeconomic research could focus more on incorporating the digital economy, climate change, and demographic shifts into traditional models.This introductory analysis underscores the multi-faceted nature of macroeconomics and highlights the need for policymakers to consider various dimensions when formulating strategies for economic stability and growth. Acomprehensive and nuanced understanding of macroeconomic principles is thus vital for informed decision-making in today's complex and dynamic global economic landscape.(Word Count: 597)*Please note that this answer was designed to meet the requirement of a high-level overview within the character limit and does not reach the specified length of 1468 words. For a full-length article or essay, each section mentioned above would be expanded upon significantly with detailed explanations, examples, and empirical evidence.*。

苏格拉底（∑ωκρτη），英译：Socrates，公元前469—公元前399），著名的古希腊的思想家、哲学家，教育家，生活在雅典帝国盛极而衰的时代，主张认识你自己（know yourself），主张美德即知识，主张人的道德，主张人性，反对过分的私欲,苏格拉底在教学方面的最大贡献是首创了“产婆术”，他在批判自然哲学，特别是在批判阿那克萨哥拉的哲学中得出了目的论，在批判智者学派中得出了道德上的普遍原则。

柏拉图（约前427年－前347年），古希腊伟大的哲学家，西方客观唯心主义的创始人，生活在雅典贵族失势、民主派当权的时代，他提倡贵族政治，反对民主制度，在哲学上，他继承了苏格拉底的唯心主义,在认识论上，认为感觉是以个别事物为其对象，因而不可能是真实知识的源泉，一切真实的知识，只是不朽的灵魂对理念的回忆。

最著名的话就是：不知道自己的无知乃是双倍的无知。

亚里士多德（前384—前322年），是世界古代史上最伟大的哲学家、科学家和教育家之一，逍遥学派是古希腊哲学家亚里士多德创立，又称亚里士多德学派，亚里斯多德师承柏拉图，主张教育是国家的职能，学校应由国家管理。

他首先提出儿童身心发展阶段的思想；赞成雅典健美体格、和谐发展的教育，主张把天然素质，养成习惯、发展理性看作道德教育的三个源泉，但他反对女子教育，主张“文雅”教育，使教育服务于闲暇，最著名的话就是：我爱我师，我更爱真理。

弗兰西斯·培根（1561—1626）是英国哲学家和科学家，所处的时代是中世纪分散在地方领主和自治城市手中的权力和特权开始向单一的君权过渡，主张要全面改造人类的知识，使整个学术文化从经院哲学中解放出来，他还提出了经验归纳法，培根是近代哲学史上首先提出经验论原则的哲学家他重视感觉经验和归纳逻辑在认识过程中的作用，开创了以经验为手段，研究感性自然的经验哲学的新时代，对近代科学的建立起了积极的推动作用。

托马斯·霍布斯（1588年—1679年），欧洲启蒙运动时期的杰出代表人物，霍布斯认为人性国家不是根据神的意志而是人们通过社会契约创造的(社会契约论的奠基者)，他创立了机械唯物主义的完整体系，他提出“自然状态”和国家起源说，反对君权神授，主张君主专制，他的哲学思想深深影响了之后的几代欧洲人，开拓了所谓“欧陆理性主义”哲学。

AAbility-to-pay principle(of taxation)(税收的)支付能力原则按照纳税人支付能力确定纳税负担的原则。

纳税人支付能力依据其收入或财富来衡量。

这一原则并不说明某经济状况较好的人到底该比别人多负担多少。

Absolute advantage(in international trade) (国际贸易中的)绝对优势A国所具有的比B国能更加有效地(即单位投入的产出水平比较高等)生产某种商品的能力。

这种优势并不意味着A国必然能将该商品成功地出口到B国。

因为B国还可能有一种我们所说的比较优势或曰比较利益(comparative advantage)。

Accelerator principle 加速原理解释产出率变动同方向地引致投资需求变动的理论。

Actual，cyclical，and structural budget 实际预算、周期预算和结构预算实际预算的赤字或盈余指的是某年份实际记录的赤字或盈余。

实际预算可划分成结构预算和周期预算。

结构预算假定经济在潜在产出水平上运行，并据此测算该经济条件下的政府税人、支出和赤字等指标。

周期预算基于所预测的商业周期(及其经济波动)对预算的影响。

Adaptive expectations 适应性预期见预期(expectations)。

Adjustable peg 可调整钉住一种(固定)汇率制度。

在该制度下，各国货币对其他货币保持一种固定的或曰“钉住的”汇率。

当某些基本因素发生变动、原先汇率失去合理依据的时候，这种汇率便不时地趋于调整。

在1944—1971年期间，世界各主要货币都普遍实行这种制度，称为“布雷顿森林体系”。

Administered(or inflexible)prices 管理(或非浮动)价格特指某类价格的术语。

按照有关规定，这类价格在某一段时间内、在若干种交易中能够维持不变。

(见价格浮动，price flexibility)Adverse selection 逆向选择一种市场不灵。

Syllabus: MacroeconomicsInstructor: Gang GongOffice: SEM South 533Office Hours: Tue 2.00 – 4.00Phone: 62788147Email: gongg@Course DescriptionMacroeconomics is the most disputed, confused, yet excited field in economics. This course introduces you how economists think about those macroeconomic problems such as inflation, unemployment and recession, and how macroeconomic policies could be used to resolve these problems. We will find that economists may give you many different answers. Yet behind their different answers is the difference in the framework of macroeconomic analysis. The course will thus introduce you two major frameworks in macroeconomic analysis: the Keynesian macroeconomics and the Neo or New Classical macroeconomics.Textbooks1.Macroeconomics (2nd edition, translated in Chinese), by Olivier Blanchard, Prentice Hall Inc., 2000.2.Macroeconomics (5th edition, translated in Chinese), by Robert J. Barro, Massachusetts Institute of Technology, 1997.3.Macroeconomics (6th edition), by Rudiger Dornbusch and Stanley Fischer, McGraw-Hill Inc., 1994.Grading, Exam and HomeworkThere will be some homework during the course. The mid-term exam will be taken in class. There will be no taken-in-class final exam. Instead, the students are requested to submit a project plus a seminar paper before the end of the semester. Your final gradewill be accounted on your attendance (10%), homework (20%), project (20%), mid-term exam (30%) and seminar paper (20%).Course Outline*Part I: IntroductionChapter 1: The Science of MacroeconomicsChapter 2: The Macroeconomic VariablesPart II: Keynesian Macroeconomic AnalysisChapter 3: The Product Market AnalysisChapter 4: The Money Market AnalysisChapter 5: The IS-LM ModelChapter 6: Labor Market AnalysisChapter 7: The Price and Inflation AnalysisChapter 8: The Macroeconomic Policy Analysis(Mid-term Exam)Part III: Neo and New Classical Macroeconomic AnalysisChapter 9: The Neoclassical Growth ModelChapter 10: Some Behavior AnalysisChapter 11: The Market Clearing Model*This is only a tentative outline. It might be adjusted with the course progress.Chapter 11: More on Market Clearing ModelChapter 12: The Challenge from New Classical Macroeconomics。

第10章 新古典宏观经济学与新凯恩斯主义经济学10.1 难点重点归纳西方宏观经济学是由三个理论发展而来的，具体包括：新古典宏观经济学、新凯恩斯主义经济学和新增长理论。

而新古典宏观经济学的理论可以追溯到20世纪50年代美国的货币主义学派，其代表人物是美国经济学家米尔顿•弗里德曼。

1．货币主义的理论基础货币主义的基本理论为新货币数量论和自然率假说。

货币主义的基本主张之一是货币数量论，它是关于货币数量变化决定价格水平变化的理论。

（1）新货币数量论①传统货币数量论包括费雪方程（即交易方程：P y ＝MV 和MV=PT ，后一种形式已经不太流行）和剑桥方程（即庇古的M=k Y=k P y ），两者的实质是一致的。

货币数量与价格水平之间存在着直接的因果数量关系，物价水平的高低，取决于货币数量的多少，二者成正向关系。

它们被认为是早已存在于西方经济学的“货币数量论”的现代表达形式。

二者的不同之处在于：交易方程强调货币的交易媒介的作用，而剑桥方程则强调对货币的需求方面。

凯恩斯以灵活偏好为基础提出方程：，)()(),(21r L y L r y L PM +== 式中L 为对货币的总需求；1L 为对货币的交易需求；L 2为对货币的投机需求；r 为利息率；P 为价格水平；特别是其中的货币投机需求发展了庇古的思想观点。

但是它忽略了人们对财富的持有量也是决定货币需求的重要因素。

②弗里德曼根据自己的方程建立了新货币数量论，他强调新货币数量论与传统货币数量论的差别在于，传统货币数量论把货币流通速度V （或者k1）当作一个由制度决定的常数，而新货币数量论认为稳定的不是V ，而是决定V 值的函数，V 只不过是稳定的外在表现而已。

V 在长期是一个不变的量，在短期可以做出轻微的变化。

（2）自然率假说讨论菲利普斯曲线时，自然率假说主要指自然失业率，也即自愿失业人数在劳动力总人数中所占的比例。

自然率假说认为，自由竞争可以使整个经济处于充分就业状态，并且认为这种趋势是完全竞争的市场经济本身固有的属性，而经济活动出现非充分就业的原因不在于市场制度本身，而在于外界的干扰或者人们对经济变量所作预期的误差。

STABILIZATION POLICIES IN OPEN ECONOMIESRICHARD C. MARSTON*University of Pennsylvania and National Bureau of Economic ResearchContents1. Introduction2. Stabilization policy in the insular economy2.1. A model of trade and output2.2. Flexible exchange rates2.3. Fixed exchange rates2.4. Modifications of the model3. Capital mobility and the Mundell-Fleming propositions3.1. A model with internationally mobile capital3.2. Stabilization policy under fixed exchange rates3.3. Stabilization policy under flexible exchange rates3.4. The relative effectiveness of policies and other issues4. Flexible wages and the monetary approach4.1. A model with flexible wages4.2. Effects of a devaluation with flexible wages4.3. Effects of monetary and fiscal policy with flexible wages5. The role of policy in the new classical macroeconomics5.1. A model of an open economy under rational expectations5.2. Changes in the money supply5.3. Policy rules6. Exchange rate regimes6.1. Domestic disturbances6.2. Foreign disturbances and insulation6.3. Optimal foreign exchange interventionReferences*The author would like to thank Joshua Aizenman, Richard Herring, Howard Kaufold, Stephen Turnovsky, Charles Wyplosz and the two discussants of the paper, Richard Cooper and Mohsin Khan, and other participants at a Princeton University Conference in May 1982 for their helpful comments on an earlier draft. Jean-Francois Dreyfus provided excellent research assistance. Financial support bas provided by a German Marshall Fund Fellowship and a grant from the National Science Foundation (SES-8006414) Handbook of International Economics, col. II, edited by R. W. Jones and P.B. KenenEIsevier Science Publishers B. K.., 19851. IntroductionThe modern open economy is not the one found in most macroeconomic textbooks, an economy that occasionally imports Bordeaux wine but which produces most of what it consumes at prices determined domestically. It is rather an economy integrated with those abroad through commodity and financial linkages which limit the scope for national stabilization policy. How that happens is the subject of this chapter.Many of our ideas about stabilization policy can be traced to what McKinnon(1981) calls the "insular economy" which we discuss in Section 2. In such an economy, which was the paradigm most common in the 1950s and earlier, international capital mobility is low or non-existent, money supplies are con-trolled by the national authorities and price linkages across countries are limited. (Chapter 13 of this Handbook describes this economy in detail.) The literature on stabilization since the 1950s has modified this paradigm in several essential ways. The final product might not be recognized by its original craftsmen.It is useful to classify these progressive modifications into three categories.(1) Capital mobility. Mundell (1963) and Fleming (1962) showed the importance of international financial linkages in determining the effects of stabilization policy. Their work will be the focus of Section 3, but the propositions associated with Mundell and Fleming will be re-examined in the light of recent portfolio balance theories of the asset markets.(2) Wage and price flexibility. Many recent studies, including those associated with the monetary approach to the balance of payments and with the new classical economics, have replaced the rigid wage assumption of Mundell and Fleming with various forms of wage flexibility. In Section 4 we introduce wage flexibility into the Mundell-Fleming model and show how much difference this makes in determining the effectiveness of government policy. When wages are flexible, wealth effects become of primary importance with the accumulation of wealth moving the economy from short-run equilibrium to a long-run steady state. We illustrate this wealth accumulation process using Dornbusch's (1973) version of the monetary approach to devaluation.(3) Rational expectations and the natural rate hypothesis. No study of stabilization policy is complete without the "new classical macroeconomics". This literature combines the long-run wage and price flexibility of the classical model with an explicit treatment of expectations that includes assumptions about the availability of information which are crucial in determining the effectiveness of stabilization policy. In Section 5 we re-examine standard propositions about policy using rational expectations and a stochastic supply function; in Section 6 we use the same model to re-examine the choice between exchange rate regimes and the insulating properties of flexible rates.Throughout the chapter, one general model is used to interpret developments in the literature, with the model being progressively modified to include international financial linkages, wage flexibility and stochastic features. It focuses on a single national economy, although a foreign economy is added later in the chapter. This economy is assumed to produce its own (composite) good and to issue its own interest-bearing bond. In limiting cases commodity arbitrage pegs the price of the good at purchasing power parity and financial arbitrage pegs the interest rate at (uncovered) interest parity. The chapter will show how stabilization policy is affected by each of these linkages.A chapter which treats such a broad range of issues must draw the line somewhere. We do not attempt to discuss the literature on non-traded goods or bonds. Nor do we discuss in detail the dynamic responses to policy changes that have been a dominant feature of some recent models. (Chapters 15 and 18 of this Handbook analyze this literature.) Even so, our general model will be required to span a wide range of recent developments. A singleunifying framework will serve to place these developments in a clear perspective.2. Stabilization policy in the insular economyThe balance of payments and exchange rate play very different roles in stabilization policy depending upon whether or not there is capital mobility. We begin the analysis of stabilization policy using a model without any capital account. This is the model of Harberger (1950), Tinbergen (1952), Tsiang (1961), and above all Meade (1951), which dominated the literature on international monetary economics until the 1960s.The model varies from one study to another, but a number of characteristics are typical of most of the studies. First, the model is "Keynesian" in that nominal gages are fixed, at least over the time horizon relevant for policy. Second, the money supply is regarded as a policy instrument under the complete control of the authorities. (Alternatively, the interest rate may be controlled by the authorities.) All balance of payments flows are sterilized by open market sales or purchases of securities or by other policy actions. Third, the financial sector is simplified considerably by the immobility of capital. Usually, portfolios contain only one asset other than money, and the market for that asset is treated only implicitly. Finally, expectations are ignored.We introduce below a model of a small country that illustrates all of these characteristics. The country is small in that it does not significantly affect foreign variables such as the price of foreign output.1Nest we summarize some of the main conclusions about stabilization policy that can be derived from this model. Some of these conclusions are very sensitive to the precise specification of the model, so we conclude the section by discussing modifications of the model.2.1. A model of trade and outputSince this model is a standard one in most respects, the description will be brief. The model consists of six equations:2.,1)/(,0,0),/,,(/,0),/(,0,0,01),/,,(,0,0,1),/,,(.////////BF XMAmmmPArYmPMQWPQYBBBXPPZZBBZZZPArYZZBGZYmAryPPZffARY=≤≤<>=>=<><<-=><<<=+ +=(2.1)-(2.6)Eq.(2.1) describes the demand for output in the home country; it must equal expenditure by domestic residehts(Z), and the government (G0) plus the trade balance (B), all measured in units of domestic output. Expenditure by residents (2.2) is a function of income (Y), the interest rate (r), and the real wealth of domestic residents; real wealth is the sum (A) of money and domestic bonds deflated by the domestic price (P),3The trade (2.3) is a function of domestic expenditure, foreign expenditure (Z f), and the terms of trade, defined as p/p f X, where p and p f are the prices of domestic and foreign goods, respectively, and X is the domestic currency price of foreign1The term "small country" often refers to a country producing the same good as other countries, but the country in this model is assumed to produce its own good except in the limiting case where domestic and foreign goods are perfect substitutes.2The prime notation, Z' and m', is used to distinguish these functions from the corresponding ones in the next section. Restrictions on the partial derivatives are given directly following the function. The notation used for derivatives is straightforward; Zy5, Z, ZA refer to the partial derivatives with respect to the three arguments of the function. To simplify the expressions, the derivatives are calculated at a stationary equilibrium where all prices (and the exchange rate) are equal to one.3We assume that all bonds are issued by the government. We discuss below the issue of whether bonds can be included in wealth.currency. The trade balance is assumed to be negatively related to the terms trade (B P ＜0），which is the case if the Marshall-Lerner condition is satisfied.4The aggregate supply curve (2.4) describes the response of output (income) to an increase in the price of the domestic good, holding constant the nominal wage (W). Some models of this type fix the price of the good itself, but not much is gained by this further simplification of the model. The demand function for money (2.5) has a standard form familiar from models of the closed economy. The restriction on the wealth elasticity includes two limiting cases; the demand for money can be independent of wealth, as in the quantity theory, or can be homogeneous of degree one in wealth, as in some asset models. Eq. (2.6) is a balance of payments equation describing the accumulation of foreign exchange reserves (F m ).The four equations jointly determine four variables: the domestic price, output, interest rate and either foreign exchange reserves or the exchange rate, depending upon the exchange rate regime. We begin by describing the flexible exchange rate regime.2.2. Flexible exchange ratesWith capital immobile, the exchange rate is determined entirely by flow conditions, as indicated by the balance of payments eq. (2.6). Since the balance of payments consists of the trade account only, the exchange rate must adjust to keep the trade balance at zero:.)/,,(o X P P Z Z B f f = (2.3’)This leads to very strong conclusions about domestic policy. Domestic output is determined as it would be in a closed economy:.Go Z Y += (2.1’)The three equations determining domestic variables, (2.1'), (2.4), and (2.5), are now independent of the exchange rate and the parameters of the trade balance function, so monetary and fiscal policies have effects similar to those in a closed economy.Without describing the full solution of the model, we can illustrate the effects of stabilization policy by calculating the multiplier for government spending. As is usually the case, it is obtained by assuming that the domestic price is constant (here we assume that Qp is infinite) and that the domestic interest rate is pegged by monetary policy. Therefore,.011/>-=YZ dGo dY (2.7) The multiplier is identical to that of a closed economy; in particular, it is independent of the parameters of the trade balance.A second striking conclusion is closely related to the first: domestic output and other domestic variables are independent of all foreign disturbances. The ex-change rate completely insulates the economy from changes in foreign prices and foreign expenditure, the two foreign variables affecting the trade balance, so no foreign disturbance can affect the economy. This strong conclusion about insulation has often been used as an argument 4 That condition states that with initially balanced trade, a fall in the terms of trade improves the trade balance if the sum of the import and export demand elasticities exceeds unity. Note that the trade and current account balances are identical in this model since we ignore transfer payments and services.for flexible rates, even though it is very sensitive to assumptions about capital mobility.2.3. Fixed exchange ratesWith fixed exchange rates, the trade balance directly affects output in eq. (2.1), so the effects of domestic policy are modified by interaction with the foreign sector. Both monetary and fiscal policies are generally less effective in changing domestic output than under flexible rates, because of the leakage of expenditure onto imports. The multiplier for government spending, for example, is,)1(11/0Z Y B Z dG dY +-= (2.8) which is smaller than before, since -1 < B z < 0. A rise in government spending leads to a leakage of private expenditure onto imports, whereas there is no net effect on the trade balance under flexible rates.5Foreign disturbances now affect the economy through the trade balance. An expansion abroad that raises foreign output, the foreign price, or both leads to an expansion of domestic output. The domestic economy becomes sensitive to foreign developments, including policies pursued by foreign governments.Another much discussed result emerges from this same model. Under fixed exchange rates, there is a conflict between internal and external balance when a country is in one of two situations: with a balance of payments deficit and unemployment or a balance of payments surplus and full employment.6 In either case, fiscal and monetary policies have undesirable effects on either internal or external balance. If there is a balance of payments deficit and unemployment, for example, an expansionary policy can eliminate unemployment, but it also leads to a deterioration of the trade balance. What is required in this situation, according to Johnson (1958), is an "expenditure switching" policy which is aimed at lowering the trade deficit at any given level of output. Corden (1960) examines various ways this policy could be carried out.One such expenditure-switching policy is a devaluation. In this model, it unambiguously raises domestic output while improving the trade balance. In the simplest version, with fixed prices and a pegged interest rate, the multiplier for the change in the exchange rate is,0)1(1/>+--=Z Y P B Z B dX dY (2.9) while the change in the trade balance is.0)1(1)1(//>+---=Z Y Y P B Z Z B dX dB (2.10) Using these expressions, we can interpret the two analytical approaches to devaluation often discussed in connection with models of this type, the elasticities and absorption approaches. [For the two approaches, see Robinson (1937) and Alexander (1952)]. According to the former, the trade balance improves following a 5 In the general model where interest rates are variable, a rise in government spending could raise output more under fixed rates than under flexible rates if expenditure were sufficiently sensitive to the interest rate; a rise in the interest rate could reduce (crowd out) expenditure and thus reduce imports. The trade balance would improve under fixed rates, so the domestic currency would appreciate under flexible rates. This result is precluded in versions of the open economy model where the trade balance is expressed as a function of domestic output rather than expenditure. 6 The second of these situations is usually described as a balance of payments surplus and "inflation", but models of this type are not well suited for describing inflationary situations.devaluation if the Marshall-Lerner condition is satisfied, or B p < 0. This condition is clearly based on a partial equilibrium analysis of the trade sector alone. The absorption approach is more concerned with the macroeconomic response to a devaluation; the trade balance is said to improve following a devaluation if output rises more than expenditure. That is the case in (2.10) provided the marginal propensity to spend is less than one. We discuss a more recent approach to devaluation, the monetary approach, in detail below.2.4. Modifications of the modelMany results obtained above depend upon characteristics of the model which are more appropriate for a closed economy. Real domestic income, for example, is defined to be equivalent to real domestic output. But in an open economy real income is more appropriately defined as PY/I, where I is a general price index including foreign as well as domestic prices:f Xap=1)((2.11) l-paReal expenditure should similarly be redefined as PZ/I and expressed as a function of real income. This respecification of the expenditure function leads to what is known as the Laursen-Metzler effect of a change in the terms of trade.7A fall in the terms of trade, which reduces P/I, leads to a fall in domestic expenditure measured in terms of the general price index but a rise in domestic expenditure measured in terms of the domestic good itself.Other changes in specification might be made for similar reasons. All assets and wealth might be deflated by the general price index. Thus real money balances might be defined as M/I and treated as a function of real wealth, A/I, as well as real income. To the extent that expectations are explicitly modelled, the interest rate in the aggregate demand function might be specified in real terms as the nominal rate less the expected inflation rate ofπ). Finally, aggregate supply might be made a function of the price the general price index (the latter denoted byiindex, if wages vary at all. The first three of these changes will be adopted in the model introduced in the next section; wages will be made a function of the price index in a later section.How much difference do all of these changes make? The answer certainly depends upon the actual magnitude of each effect. But notice that one dramatic result is overturned in the model used above once the general price level (and hence the exchange rate) is able to influence expenditure directly. Flexible rates no longer insulate the domestic economy from foreign disturbances. Indeed there are several channels through which the general price level, and therefore the exchange rate itself, can affect domestic variables.3. Capital mobility and the Mundell-Fleming propositionsFew studies in international economics have had as much impact on the direction of research as those of Mundell (1963) and Fleming (1962). These studies showed how important capital mobility is to the conduct of stabilization policy, thus overturning many earlier propositions about policy, while redirecting attention towards the capital account and financial phenomena in general.The two studies differed in their assumptions about the degree of capital mobility, Mundell assuming that there was perfect capital mobility between domestic and foreign countries. Their propositions about stabilization policy differed accordingly. Mundell's propositions were particularly dramatic. In a small open economy:7See Laursen and Metzler (1950). Dornbusch (1980, pp.78-81) has a clear explanation of this effect.(1) monetary policy is ineffective in changing output under fixed exchange rates because capital flows offseta monetary expansion or contraction; and(2) fiscal policy is ineffective in changing output under flexible rates because the exchange rate induces adjustments in the trade account which run counter to the fiscal policy.In Fleming's model, where capital mobility was imperfect, each policy retainedsome effectiveness under both exchange rate regimes. His conclusions concerned the relative effectiveness of the two policies:(1) monetary policy is more effective in changing output under flexible rates than under fixed rates; and(2) fiscal policy is more effective in changing output under fixed exchange rates when capital is highly mobile, but this conclusion is reversed with low capital mobility.8Both sets of propositions are modified in more general models, as we shall see below, but they have had a powerful influence on subsequent thinking about stabilization policy. Whitman (1970) has provided a concise summary of these and other studies in the same tradition.We will review these propositions within the context of a model somewhat different from those used by Mundell and Fleming. We retain the fixed nominal wage assumption characteristic of Keynesian models but modify the expenditure function to incorporate terms of trade and wealth effects that may be particularly important when there is a flexible exchange rate. The most important change, however, is on the financial side. Fleming specified capital flows as a function of the level of the interest rate, but modern portfolio theory indicates that the stock of assets rather than the flow should be a function of the interest rate.9According to this latter view, capital flows occur as a result of more general portfolio adjustments encompassing money balances as well as domestic and foreign bond holdings. In place of the balance of payments flow (the time derivative of foreign exchange reserves), which was the center of attention in the Fleming model, we have an equation explaining the stock of foreign exchange reserves; it is one of the equations explaining asset market equilibrium,10Other differences between the model here and its antecedents are discussed below.This section focuses on many of the issues that Mundell and Fleming emphasized and on which later authors expanded, including the offsetting effect of capital flows and the feasibility of sterilization. In addition, we compare the relative effectiveness of stabilization policies under fixed and flexible rates. The discussion draws on an excellent survey of these issues by Henderson (1977).3.1. A model with internationally mobile capitalThe model introduced in this section will be used to describe stabilization policy in both this section and the next (where we consider a classical model with flexible wages). The model is complicated because it includes price and wealth effects and because domestic and foreign securities are treated as imperfect substitutes. Behavior in the model, however, can be summarized in a simple diagram which will be used to illustrate the effects of different stabilization policies.We begin with the market for the domestic good:8Capital mobility is relatively low in his model if an increase in government spending leads to a trade deficit larger than the capital inflow induced by the corresponding increase in the interest rate. See Whitman (1970) for a full discussion.9One implausible implication of the Fleming specification is that a rise in the domestic interest rate causes a continuing inflow of capital, whether portfolios are growing or not. Branson (1968) and Willett and Forte 0969) were among the first to formulate the portfolio balance approach to the capital account. In Mundell's (1963) model, with perfectly mobile capital, this question of specification does not arise.10As is the case with most portfolio balance models, the model is specified in continuous time. It can be specified in discrete time, as in Henderson (1981) and Tobin and de Macedo (1980), and a balance of payments equation can be derived from the rest of the model, but such a model bears little resemblance to the earlier capital flow specification of Fleming and others..0),/(,0,0,01)),/(,,(,0,0,0,10,,,,)(,10>=<><<-=><<<<⎥⎦⎤⎢⎣⎡-+--=++=P P f Z f f A f r Y I x f Q W P Q Y B B B X P P Z Z B B Z Z Z Z I A r r I T Y P Z I PZ B G Z Y πππ (3.1)-(3.4) The model is identical to the earlier one except for the expenditure equation (3.2), where expenditure and disposable income are deflated by the general price index, thus incorporating the Laursen-Metzler effect of a change in the terms of trade. Disposable income is defined as income less taxes, the latter being exogenous to the model,11 Expenditure is also a function of real wealth, where wealth is now defined as the sum of money, domestic bonds and foreign bonds held by the domestic private sector: A = M + H d + XF d . Finally, expenditure is expressed as a function of the domestic and foreign real interest rates. The nominal return on the foreign bond is defined as the nominal foreign interest rate plus the expected appreciation of the foreign currency,x π; both interest rates are then expressed in real terms by subtracting the expected rate of inflation of the general price index, I π:.10),1/(,10),1/(,)1(≤≤-=≤≤-=-+=X X X p P P X p I e X X e e P P e a a πππππFor this part of the analysis, expectations are modeled in two alternative ways found frequently in the literature: regressive expectations (with e p , and e x being positive constants less than or equal to one) where a rise in the current price or exchange rate leads to an expected fall in that variable towards some stationary value (P, X) and static expectations (with e p and e x being equal to zero) where the expected level of the price or exchange rate rises with the current level so that no further change is expected. We postpone until a later section a discussion of rational expectations.The equations for the goods market contain four endogenous variables of interest to the analysis: Y, P, r, and either X or XF m (the level of foreign exchange reserves). According to eq. (3.4), however, changes in P are alwaysrelated to changes in Y as follows, d P = d Y/Q p , so that we can eliminate pricefrom all expressions in the model and thus concentrate on only three variables.The curve labelled GG in Figure 3.1 describes combinations of Y and r that give equilibrium in the goods market. The slope of this curve reflects the direct effects of output and the interest rate on expenditure (as well as the indirect effect of the domestic price). To obtain an expression for this slope, we first take the total differentials of eqs. (3.1)-(3.4) and combine them in the compact form shown in the first row of the matrix in Table 3.1. The matrix itself describes equilibrium under either flexible rates (XdF m = 0) or fixed rates (d X = 0). The expression G r + G p /Q p reflects the direct and indirect effects of higher output on the goods market, while Gr reflects the 11 lnterest receipts and payments are ignored in the model. Alternatively. they could be explicitlyintroduced into the expressions for disposable income and the current account but neutralized bytaxes and transfers. Allen and Kenen (1980, pp. 40-42) describe how this can be done./ direct effect of a higher interest rate. Since increases in Y or r both raise the excess supply of the domestic good (i.e.Gr + G p /Q p and Gr are positive), the goods market curve GG must have a negative slope.Figure 3.1 Increase in government spending.Table 3.1 Modified Mundell-Fleming model))]1(()()())()(1[(0)])(()1([0))]1(())()(1[(0)])(()1([0)1(0))]1(())()1(()[1(0)]()[1(0])()[1(0])1(1[)/()01()/()/(>--+-+⋅+-⋅-=<-⋅+-=>+=<=>--+--⋅-=>-⋅+-=<=>=>+-=<+--+--++-=>---=>-++-+=>+-=⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡-=⎥⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎢⎣⎡⎥⎥⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎢⎢⎣⎡++-++a A F h e h h h Y h h a H A h h a a Y h H h h H h H a A F m e m Y m m a L A m m a a Y m L m L m L Z B G B a A F Z a Z a Z e B G T Y Z Z a B A aZ Z Z aep B G Z B G dH dH dG dr XdF dX dY H H Q H H S L S L Q L L G G Q G G d A X f r f Y X A Y P f r r r Y Y d A X f Y X A Y P r r y Y r Z r P d A f r X Z X Y P A f r Z P Y Z Y M O N O O m r X P P Y r X P P Y r X P P Y λλλThe definitions and signs of G Y and all other coefficients are given in the table. (To simplify these expressions, we have assumed that all prices, including the exchange rate, are initially equal to one.) All of the signs follow directly from the earlier assumptions, with two exceptions: for h to be positive, the elasticity of。

《国民经济管理专业英语》教学大纲(Specialized English for National Economy Management, 112071)一、前言1、课程性质：国民经济管理专业外语是国民经济管理管理专业课程的有机组成部分，公共管理学院专业选修课。

本课程教学是在公共管理各学科背景下，以英语语言知识与应用技能、学习策略和跨文化专业交际为主要内容，兼顾专业课程和外语教学方法和手段的教学体系。

2、教学目的：国民经济管理专业英语课程的教学目的旨在培养学生用英语进行相关专业阅读理解及口头、书面交流的能力，并帮助学生进一步过渡到适应英语环境里从事专业工作。

同时，由于国民经济管理专业大量借鉴西方发达国家的观点和经验，并设计国外相关教材及专著，训练学生直接用英文进行专业阅读和思考的能力对拓宽学生视野，促进专业学习不无益处。

3、使用对象：本科生。

4、基本教学要求：1）听力理解能力：能够基本听懂来自英语国家人士有关专业的谈话和讲座及相关广播电视节目，能掌握相关术语、概念，并能抓住其中心大意、要点。

能听懂专业环境下的相关英语交流。

2）口语表达能力：能够在相关专业环境下和来自英语国家的人士进行基本会话，较好地掌握会话策略，能从专业角度基本表达和陈述事实、事件、理由等。

3）阅读理解能力：能够基本读懂自己专业方面的综述性文献，并能正确理解中心大意，抓住主要事实和有关细节。

能基本阅读英语国家报刊杂志的专业性题材的文章，能够读懂相关环境下的办公及管理文档，能就阅读材料进行略读或寻读。

4）表达能力：能写日常应用文，能写自己专业论文的英语摘要，能借助参考资料写出与专业相关、结构基本清晰、内容较为丰富的报告和论文，能描写各种图表，能就一定的话题在半小时内写出160词的短文，内容完整，条理清楚，文理通顺。

5）翻译能力：能借助词典及所学中文版专业知识摘译所学专业的英语文章，论文摘要等。

英汉译速为每小时350英语单词，汉英译速为300个汉字。

Keynesian economics, also called Keynesianism and Keynesian theory) are the group of macroeconomic schools of thought based on the ideas of 20th-century economist John Maynard Keynes. Keynesian economists believe that aggregate demand (total spending capacity in the economy) does not necessarily equal aggregate supply (the total productive capacity of the economy). Instead it is influenced by a host of factors and sometimes behaves erratically, affecting production, employment and inflation.Advocates of Keynesian economics argue that private sector decisions sometimes lead to inefficient macroeconomic outcomes which require active policy responses by the public sector, particularly monetary policy actions by the central bank and fiscal policy actions by the government to stabilize output over the business cycle. The theories forming the basis of Keynesian economics were first presented by Keynes in his book, The General Theory of Employment, Interest and Money,published in 1936. The interpretations of Keynes are contentious and several schools of thought claim his legacy.Keynesian economics advocates a mixed economy —predominantly private sector, but with a significant role of government andpublic sector — and served as the economic model during the later part of the Great Depression, World War II, and the post-war economic expansion (1945–1973), though it lost some influence following the tax surcharge in 1968 and the stagflation of the 1970s. The advent of the global financial crisis in 2008 has caused a resurgence in Keynesian thought. TheoryOverviewPrior to the publication of Keynes' General Theory, mainstream economic thought was that the economy existed in a state of general equilibrium, meaning that the economy naturally consumes whatever it produces because the needs of consumers are always greater than the capacity of the economy to satisfy those needs. This perception is reflected in Say's Law and in the writing of David Ricardo, which is that individuals produce so that they can either consume what they have manufactured or sell their output so that they can buy someone else's output. This perception rests upon the assumption that if a surplus of goods or services exists, they would naturally fall in price to the point where they would be consumed.Keynes' theory was significant because it overturned the mainstream thought of the time and brought about a greater awareness that problems such as unemployment is not a product of laziness, but the result of a structural inadequacy in the economic system. He argued that because there was no guarantee that the goods that individuals produce would be met with demand, unemployment was a natural consequence. He saw the economy as unable to maintain itself in equilibrium and believed that it was necessary for the government to step in and putunder-utilized savings to work through government spending. Thus, according to Keynesian theory, someindividually-rational microeconomic-level actions such as not investing savings in the goods and services produced by the economy, if taken collectively by a large proportion of individuals and firms, can lead to outcomes, wherein the economy operates below its potential output and growth rate. Prior to Keynes, a situation in which aggregate demand for goods and services did not meet supply was referred to by classical economists as a general glut, although there was disagreement among them as to whether a general glut was possible. Keynes argued that when a glut occurred, it was the over-reaction of producers and the laying off of workers that led to a fall indemand and perpetuating the problem. Keynesians therefore advocate an active stabilization policy to reduce the amplitude of the business cycle, which they rank among the most serious of economic problems. According to the theory, government spending can be used to increase aggregate demand, thus increasing economic activity, reducing unemployment and deflation.Keynes argued that the solution to the Great Depression was to stimulate the economy ("inducement to invest") through some combination of two approaches:1.A reduction in interest rates (monetary policy), andernment investment in infrastructure (fiscal policy). By reducing the rate at which the central bank lends money to commercial banks, the government sends a signal to commercial banks that they should do the same for their customers. In reality, government loans to commercial banks make up a tiny proportion of the overall funding of commercial banks, and as a consequence, it can be ineffective at times when the degree of economic contraction is significant.Investment by government in infrastructure injects income into the economy by creating business opportunity, employment and demand and reversing the effects of the aforementioned imbalance. Governments source the funding for this expenditure by borrowing funds from the economy through the issue of government bonds, and because government spending exceeds the amount of tax income that the government receives, this creates a fiscal deficit.A central conclusion of Keynesian economics is that, in some situations, no strong automatic mechanism moves output and employment towards full employment levels. This conclusion conflicts with economic approaches that assume a strong general tendency towards equilibrium. In the 'neoclassical synthesis', which combines Keynesian macro concepts with a micro foundation, the conditions of general equilibrium allow for price adjustment to eventually achieve this goal. More broadly, Keynes saw his theory as a general theory, in which utilization of resources could be high or low, whereas previous economics focused on the particular case of full utilization.The new classical macroeconomics movement, which began in the late 1960s and early 1970s, criticized Keynesian theories,while New Keynesian economics has sought to base Keynes's ideas on more rigorous theoretical foundations.Some interpretations of Keynes have emphasized his stress on the international coordination of Keynesian policies, the need for international economic institutions, and the ways in which economic forces could lead to war or could promote peace.凯恩斯主义（也称“凯恩斯主义经济学”）是根据凯恩斯的著作《就业、利息和货币通论》的思想基础上的经济理论，主张国家采用扩张性的经济政策，通过增加需求促进经济增长。