2福利經(jīng)濟(jì)學(xué)基礎(chǔ)

1、第二講 財(cái)政學(xué)的福利經(jīng)濟(jì)學(xué)基礎(chǔ)（標(biāo)準(zhǔn)分析工具） 政府的經(jīng)濟(jì)活動(dòng)多種多樣，評(píng)價(jià)種種不同的政府行為的合理性需要有一個(gè)一般性框架。 財(cái)政學(xué)領(lǐng)域的大多數(shù)專(zhuān)家使用的評(píng)價(jià)分析框架是福利經(jīng)濟(jì)學(xué)。 本講介紹福利經(jīng)濟(jì)學(xué)的根本內(nèi)容，用以區(qū)分哪些情況市場(chǎng)運(yùn)作自發(fā)帶來(lái)理想結(jié)果，哪些情況市場(chǎng)無(wú)法產(chǎn)生理想結(jié)果。 1第二講 財(cái)政學(xué)的福利經(jīng)濟(jì)學(xué)基礎(chǔ)一、福利經(jīng)濟(jì)學(xué) （ Welfare Economics） 1 Pure Economy Exchange 2 Production Economy二、福利經(jīng)濟(jì)學(xué)第一根本定理三、 公平與福利經(jīng)濟(jì)學(xué)第二根本定理四、 市場(chǎng)失敗五、 福利經(jīng)濟(jì)學(xué)的局限2一、福利經(jīng)濟(jì)學(xué) 福利經(jīng)濟(jì)學(xué): The

2、branch of economic theory concerned with the social desirability of alternative economic state.31.簡(jiǎn)單經(jīng)濟(jì)交換 （沒(méi)有生產(chǎn)）埃奇沃斯盒形圖Edgeworth Box帕累托效率Pareto efficient allocation: No person can be better off without making another person worse off.帕累托改進(jìn)Pareto improvement: a reallocation of resources that makes one

3、 person better off without making anyone else worse off.契約曲線Contract curve: the locus of all the Pareto efficient points.Pareto efficiency requires that the marginal rate of substitution be equal for all consumers 4Edgeworth Box: A device used to depict the distribution of goods in a two good-two pe

4、rson world.5無(wú)差異曲線 Indifference curves in an Edgeworth Box6Making Adam better off without Eve becoming worse off7Making Eve better off without Adam becoming worse off8Making both Adam and Eve better off9Starting from a different initial pointEdgeworth BoxAdamEve00srApples per yearFig leaves per yearA

5、gEggp1pEp2Ap2p2p3p4k10Contract curve: The locus of all the Pareto efficient points.(契約曲線)Edgeworth BoxAdamEve00srApples per yearFig leaves per yearAgEggp1pEp2Ap2p2p3p4The contract curve11Pareto Efficiency in Consumption消費(fèi)效率條件MRSaf = MRSaf 在純交換經(jīng)濟(jì)下，帕累托效率的實(shí)現(xiàn)條件為社會(huì)所有成員的邊際替代率相等AdamEve122 生產(chǎn)經(jīng)濟(jì)Production Ec

6、onomy（有生產(chǎn)，有交換） 生產(chǎn)可能性曲線The production possibilities curve邊際轉(zhuǎn)換率The marginal rate of transformation 產(chǎn)品組合效率條件Efficiency conditions with variable production 13生產(chǎn)可能性曲線Production possibilities curve: A graph that shows the maximum quantity of one output that can be produced, given the amount of the other o

7、utput.14斜率=MRS消費(fèi)者為了多消費(fèi)一個(gè)蘋(píng)果，愿意放棄幾片無(wú)花果葉消費(fèi)者無(wú)差異曲線蘋(píng)果無(wú)花果葉60100生產(chǎn)可能性曲線斜率=MRT為了多生產(chǎn)一個(gè)蘋(píng)果需要放棄幾片無(wú)花果葉產(chǎn)品組合效率要求MRS = MRTCEfficiency Conditions with variable production15邊際轉(zhuǎn)換率Marginal Rate of TransformationMRTaf = Marginal rate of transformation of apples for fig leavesMRTaf = MCa/MCf16帕累托效率條件MRTaf = MRSaf = MRSafM

8、Ca/MCf = MRSaf = MRSafAdamEveAdamEve17二、福利經(jīng)濟(jì)學(xué)第一根本定理The First Fundamental Theorem of Welfare EconomicsAs long as producers and consumers act as perfect competitors, that is, take prices as given, then under certain conditions, a Pareto efficient allocation of resources emerges.只要生產(chǎn)者和消費(fèi)者扮演完全競(jìng)爭(zhēng)者的角色，即接受

9、給定的價(jià)格,競(jìng)爭(zhēng)的經(jīng)濟(jì)會(huì)“自動(dòng)實(shí)現(xiàn)帕累托有效的資源配置。 18三、 Fairness and the second fundamental theorem of welfare economics If properly functioning competitive markets allocate resources efficiently, what role does the government have to play in the economy?效率不是決定某種資源配置好壞的惟一標(biāo)準(zhǔn)。即使經(jīng)濟(jì)實(shí)現(xiàn)了帕累托效率，為了效用分配更加公平，政府仍有必要干預(yù)經(jīng)濟(jì)。19Efficiency

10、 versus EquityEdgeworth BoxAdamEve00srApples per yearFig leaves per yearqp5p320效用可能性曲線: It shows the maximum amount of one persons utility given the other individuals utility level.Eves utilityAdams utilityUUp3qp521社會(huì)無(wú)差異曲線Social Indifference CurveEves utilityAdams utilityW = F(UAdam, UEve)Increasing

11、socialwelfare22Maximizing Social WelfareEves utilityAdams utilityiiiiii23福利經(jīng)濟(jì)學(xué)第二根本定理： 在完全競(jìng)爭(zhēng)的市場(chǎng)條件下，政府所要做的事情是改變個(gè)人之間稟賦的初始分配狀態(tài)，其余的一切都可以由市場(chǎng)來(lái)解決。每一種具有帕累托效率的資源配置都可以通過(guò)市場(chǎng)機(jī)制實(shí)現(xiàn)。24四、市場(chǎng)失敗 Market Failure市場(chǎng)勢(shì)力 Market Power壟斷 monopoly市場(chǎng)不存在 Nonexistence of Markets信息不對(duì)稱(chēng) asymmetric information外部性 externality公共商品 public

12、good25OverviewThe First Welfare Theorem of states that a properly working competitive economy generates a Pareto efficient allocation of resources without any government intervention. However, it is not obvious that an efficient allocation of resources is per se socially desirable; some argue that f

13、airness must also be considered. Moreover, competition may not hold and not all markets may exist in real-world economies. Hence, the market-determined allocation of resources is unlikely to be efficient. There are, then opportunities for government to intervene and enhance economic efficiency. 26Ov

14、erviewThe fact that the market-generated allocation of resources is imperfect does not necessarily mean the government is capable of doing better.Moreover, governments , like people, can make mistakes.27五、福利經(jīng)濟(jì)學(xué)的局限Individualistic outlook: Welfare Economics is based on an individualistic social philosophy.Merit goods: A commodity that ought to be provided even if people do not demand it 28Results orientation: Welfare Economics concerns only the results, it does not pay much attenti