《中級微觀經(jīng)濟(jì)學(xué)》pr8e_ch03ly.ppt

1、Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e.,* of 40,3.1Consumer Preferences 3.2Budget Constraints 3.3Consumer Choice 3.4Revealed Preference 3.5Marginal Utility and Consumer Choice 3.6Cost-of-Living Indexes,C H A P T E R 3,Prepared by: Fernando Quijano, Illustrator,Co

2、nsumer Behavior,CHAPTER OUTLINE,第三章 消費(fèi)者行為consumer behavior,第三章,3.1消費(fèi)者偏好 3.2預(yù)算約束 3.3消費(fèi)者選擇 3.4顯示偏好 3.5邊際效益與消費(fèi)者選擇 3.6生活成本指數(shù),消費(fèi)者行為,消費(fèi)者行為理論 描述消費(fèi)者如何在不同的商品和服務(wù)之間分配其收入以使幸福最大化。,下述三個獨(dú)立的步驟是理解消費(fèi)者行為的最佳方法: 消費(fèi)者偏好 預(yù)算約束 消費(fèi)者選擇,Consumer Preferences,3.1,Market Baskets,MARKET BASKET,UNITS OF FOOD,UNITS OF CLOTHING,Some B

3、asic Assumptions about Preferences 有關(guān)偏好的一些基本假設(shè),Completeness: Preferences are assumed to be complete. 完備性:偏好是完備的， Note that these preferences ignore costs.,Transitivity: Preferences are transitive. 傳遞性:偏好是可傳遞的。,More is better than less: Goods are assumed to be desirablei.e., to be good. 越多越好,EAG.,Ind

4、ifference Curves 無差異曲線, indifference curve Curve representing all combinations of market baskets that provide a consumer with the same level of satisfaction.,Indifference Maps無差異曲線簇, indifference map Graph containing a set of indifference curves showing the market baskets among which a consumer is i

5、ndifferent.,INDIFFERENCE CURVES CANNOT INTERSECT,FIGURE 3.4,The Shape of Indifference Curves,The Marginal Rate of Substitution 邊際替代率(MRS),為獲得一個單位的一種商品，必須放棄的另外一個商品的數(shù)量,CONVEXITY 擬凸性 When the MRS diminishes along an indifference curve, the curve is convex.,Perfect Substitutes and Perfect Complements 完全

6、替代品與完全互補(bǔ)品,完全替代品 當(dāng)一種商品對另一種商品的邊際替代率是常數(shù)時 ，兩種商品即為 完全替代品。, 完全互補(bǔ)品 當(dāng)兩種商品的邊際曲線是直角形狀，他們的MRS為0或1，此時兩商品為完全互補(bǔ)商品。,bad 厭惡品 少一點(diǎn)比多一點(diǎn)好的商品,PERFECT SUBSTITUTES AND PERFECT COMPLEMENTS,UTILITY AND UTILITY FUNCTIONS 效用和效用函數(shù), utility Numerical score representing the satisfaction that a consumer gets from a given market b

7、asket. 效用 消費(fèi)者從一個市場籃子中得到的滿足程度的數(shù)值表示。,u (F,C ) =FC,ORDINAL VERSUS CARDINAL UTILITY 序數(shù)效用和基數(shù)效用, 序數(shù)效用 能產(chǎn)生對市場籃子排序的效用函數(shù)被稱為序數(shù)效用函數(shù)。, 基數(shù)效用 能描述一個市場籃子在多大程度上比另一個更受偏好的的效用函數(shù)。,Market baskets associated with the budget line F + 2C = $80, 預(yù)算線 購買商品F和C的總支出等于收入的情況下，所有的商品F和C的組合。,Budget Constraints 預(yù)算約束,3.2,(3.1),(3.2),The

8、 Effects of Changes in Income and Prices 收入和價格變化的效應(yīng),價格變化的效應(yīng),FIGURE 3.12,Consumer Choice 消費(fèi)者選擇,3.3,效用最大化的菜籃子必須滿足兩個條件: 它特必須位于預(yù)算線上. 他必須能給予消費(fèi)者其最偏好的商品和服務(wù)的組合, marginal benefit 邊際效益 額外一單位商品的消費(fèi)所對應(yīng)的收益, marginal cost 邊際成本 額外一單位商品的消費(fèi)所對應(yīng)的成,邊際效益=邊際成本,滿足程度最大化的點(diǎn)符合： MRS = PF/PC,(3.3),角落點(diǎn) 在一個市場籃子中消費(fèi)者的邊際替代率位不等于價格比的情況

9、。 （LY: equality is allowed, not strict),FIGURE 3.15,Corner Solutions 角落點(diǎn),如果一位消費(fèi)者選擇兩個菜籃子中的一個，那么消費(fèi)者未必偏好那個被選中的菜籃子。（why? budget） 如果一位消費(fèi)者選擇兩個菜籃子中的一個，并且被選中的菜籃子比另一個更貴，那么消費(fèi)者必定偏好那個被選中的市場籃子。,Revealed Preference,3.4, marginal utility (MU) 邊際效用 對從消費(fèi)額外一單位的商品中所獲得的額外滿足的度量, diminishing marginal utility 邊際效用遞減 隨著一種商

10、品的消費(fèi)越來越多，額外的數(shù)量的消費(fèi)所帶來的效用增加也越來越小。,Marginal Utility and Consumer Choice邊際效用與消費(fèi)者選擇,3.5,邊際效用與消費(fèi)者選擇,邊際相等原則 是花在所有商品上的每一美元所帶來的邊際效用相等。,LY: max U=U(x1,x2) st p1x1+p2x2=M three ways to explain: math, figure and language, ideal cost-of-living index Cost of attaining a given level of utility at current prices re

11、lative to the cost of attaining the same utility at base-year prices. 理想生活成本指數(shù) 就是以當(dāng)前的價格達(dá)到一個給定效用水平所花成本相對于基期價格所達(dá)到相同效果所花成本的比值.,Cost-of-Living Indexes生活成本指數(shù),3.6, cost-of-living index Ratio of the present cost of a typical bundle of consumer goods and services compared with the cost during a base period.

12、 生活成本指數(shù) 指商品和服務(wù)的典型消費(fèi)組合在當(dāng)期的成本與基期的成本之比,Laspeyres Index, Laspeyres price index Amount of money at current year prices that an individual requires to purchase a bundle of goods and services chosen in a base year divided by the cost of purchasing the same bundle at base-year prices. 拉氏物價指數(shù) 以當(dāng)期價格購買一個基期選定的商

13、品服務(wù)組合所需的貨幣數(shù)與以基期價格購買同一組合商品所需的貨幣數(shù)商.,The Laspeyres index overcompensates Rachel for the higher cost of living, Paasche index Amount of money at current-year prices that an individual requires to purchase a current bundle of goods and services divided by the cost of purchasing the same bundle in a base year. 帕氏指