微观经济学清华大学7 020927

1、Chapter Fifteen,Market Demand,From Individual to Market Demand Functions,Think of an economy containing n consumers, denoted by i = 1, ,n. Consumer is ordinary demand function for commodity j is,From Individual to Market Demand Functions,When all consumers are price-takers, the market demand function for commodity j is,From Individual to Market Demand Functions,p1,p1,p1,20,15,35,p1,p1”,p1,p1”,p1,p1”,The “horizontal sum” of the demand curves of individuals A and B.,Elastici。

2、Chapter Seven,Revealed Preference 显现性偏好,What Is the Question of the Chapter?,Suppose we observe a collection of a consumers choices, can we discover his/her preference?Is this possible at all? If so, under what conditions is this possible?(This is the reverse question of finding the optimal choice),Digression: Science vs. Engineering (对比科学家思维与工程师思维）,找问题与解问题的不同 要对问题提问题务虚与务实的不同解释世界与改造世界的不同 旁观者与参与者的不同,Maintained Assumptions on Prefer。

3、Chapter Fourteen,Consumers Surplus,Monetary Measures of Gains-to-Trade,You can buy as much rice as you wish at RMB1 per kilogram once you enter the gasoline market. Q: What is the most you would pay to enter the market?,A: You would pay up to the dollar value of the gains-to-trade you would enjoy once in the market. How can such gains-to-trade be measured?,Monetary Measures of Gains-to-Trade,Three such measures are: Consumers Surplus Equivalent Variation, and Compensating Variation. Only in o。

4、课 程 简 介,高级微观经济学,任课教师：武康平 2008年9月15日,课程教材,高级微观经济学 武康平 编著 清华大学出版社，2001年版,参考书 Microeconomic Theory,by A. Mas-Colell, M. D. Whinston & J. R. Green, Oxford University Press(1995),课程安排,上课日期：9月17日 12月31日9：17、24；10：1、8、15、22、29；11：5、12、19、26；12：3、10、17、24、31考核方式：平时考察 + 期末考试平时考察：作业、论文、课堂、考勤 期末考试：闭卷成绩评定：平时成绩20% + 考试成绩80%课程助教：狄剑光dijg.06sem.tsinghua.edu.cn,学院主页课程。

5、Lecture 2,经济行为空间,2,Topics to be Discussed,本讲是经济学学走向高级阶段的第一步，将反思经济活动中的人、市场和商品，并借助现代数学工具，使这些基本概念得以提升和科学化，为后面的分析奠定基础。 本讲的内容安排如下：,经济人：主要是分析经济活动主体的含义，分析经济行为的理性，把经济活动者与现实人加以区分。 市场结构：解析市场的实质以及市场组织的结构特点。 商品空间：主要是分析和表述经济行为表现的一般特点。 价值与价格：主要是从实证角度去看待价值问题，给出一套分析工具，并要把价值表现形式与市场结构联系起。

6、Chapter Five,Choice 消费者最优选择,Where Are We Doing in This Chapter?,After modeling a consumers choice set and his preference (represented by utility functions), we now put them together and model how he/she makes optimal choice. In mathematical terms, this is a constrained maximization problem; In economics, this is a rational choice problem.,Rational Constrained Choice,Affordable bundles,x1,x2,More preferred bundles,Rational Constrained Choice,The most preferred affordable bundle is called。

7、Chapter Ten,Intertemporal Choice,What Are We Doing in this Chapter?,We apply our basic framework of consumer choice to study issues of choices across different time periods;Again, in terms of theoretical framework, not much is new!,What Are the Questions?,Persons often receive income in “lumps”; e.g. monthly salary. How is a lump of income spread over the following month (saving now for consumption later)? Or how is consumption financed by borrowing now against income to be received at the end。

8、Chapter Fourteen,Consumers Surplus,Monetary Measures of Gains-to-Trade,You can buy as much rice as you wish at RMB1 per kilogram once you enter the gasoline market. Q: What is the most you would pay to enter the market?,A: You would pay up to the dollar value of the gains-to-trade you would enjoy once in the market. How can such gains-to-trade be measured?,Monetary Measures of Gains-to-Trade,Three such measures are: Consumers Surplus Equivalent Variation, and Compensating Variation. Only in o。

9、Chapter Nine,Buying and Selling,What Are We Doing in this Chapter?,We expand our basic consumer choice framework to include the possibility that consumers can sell something to generate income.Again, in terms of theoretical framework, nothing is new.,Endowments 禀赋,The list of resource units with which a consumer starts is his endowment. A consumers endowment will be denoted by the vector (omega).,Endowments,E.g. states that the consumer is endowed with 10 units of good 1 and 2 units of good 。

10、Chapter Sixteen,Equilibrium,Market Equilibrium,A market is in equilibrium when total quantity demanded by buyers equals total quantity supplied by sellers.,Market Equilibrium,p,D(p), S(p),q=D(p),Market demand,Market supply,q=S(p),p*,q*,D(p*) = S(p*); the market is in equilibrium.,An Example,At the equilibrium price p*, D(p*) = S(p*). That is,which gives,and,Market Equilibrium,Can we calculate the market equilibrium using the inverse market demand and supply curves? Yes, it is the same ca。

11、Chapter Two,Budget Constraint,Where are We in the Course?,We are working on the 1st of the 3 components of microeconomics: Consumer behavior, production theory, and market.There are three elements of consumer behavior: budget constraint, preference, and choices.,Consumption Choice Sets,A consumption choice set is the collection of all consumption choices available to the consumer. What constrains consumption choice? Budgetary, time and other resource limitations.,Budget Constraints,Q: When is a 。

12、Chapter Three,Preferences 消费者偏好,Where Are We in the Course?,We are studying the 1st of the three blocks of microeconomics: Consumer behavior, production theory, and market equilibrium Within the 1st block, we are working on the 2nd of the three components: choice set, preference, and consumer demand,What Do We Mean by Preference? (偏好),It refers to the ordered relationship among alternative choices given by an economic agent.In most economic literature, consumer preference is treated as th。

13、Chapter Eight,Slutsky Equation,What Are We Doing in this Chapter?,We take a further look at the comparative statics of demand function with respect to prices; We divide the changes in demand due to price changes into two effects: Substitution effect; Income effect? Why? Deeper economic intuition.,Effects of a Price Change,What happens when a commoditys price decreases? Substitution effect: the commodity is relatively cheaper, so consumers substitute it for now relatively more expensive other co。

14、Chapter Fifteen,Market Demand,From Individual to Market Demand Functions,Think of an economy containing n consumers, denoted by i = 1, ,n. Consumer is ordinary demand function for commodity j is,From Individual to Market Demand Functions,When all consumers are price-takers, the market demand function for commodity j is,From Individual to Market Demand Functions,p1,p1,p1,20,15,35,p1,p1”,p1,p1”,p1,p1”,The “horizontal sum” of the demand curves of individuals A and B.,Elastici。

15、Chapter One,The Market - Appreciating Economic Modeling,The Purpose of this Chapter,To begin to understand the art of building an economic model To begin to understand three basic elements of modeling in economics: Purpose Simplification through assumptions Value judgment,The Purpose of an Economic Model,The purpose of an economic model is to help provide precise insights (精确的洞察力）on a specific economic phenomenon. Thus: Different phenomena needs different model; Simplification by assumpti。

16、Chapter Four,Utility 效用,What Do We Do in This Chapter?,We create a mathematical measure of preference in order to advance our analysis.,Utility Functions,A preference relation that is complete, reflexive, transitive can be represented by a utility function.,Utility Functions,A utility function U(x) represents a preference relation if and only if: x x” U(x) U(x”) x x” U(x) U(x”) x x” U(x) = U(x”).,p,p,Utility Functions,Utility is an ordinal (i.e. ord。

17、Chapter Thirteen,Risky Assets,Main Issue,Mean-Variance Utility Budget Constraints for Risky Assets Measuring Risk Capital Asset Pricing Model,Mean of a Distribution,A random variable (r.v.) w takes values w1,wS with probabilities 1,.,S (1 + + S = 1). The mean (expected value) of the distribution is the average value of the r.v.;,Variance of a Distribution,The distributions variance is the r.v.s av. squared deviation from the mean;Variance measures the r.v.s variati。

18、Chapter Twelve,Uncertainty,Main Issue,A state-contingent consumption plan Preferences Under Uncertainty and Expected utility Risk-aversion, risk-loving, and risk-neutralityCompetitive Insurance,Uncertainty is Pervasive,What is uncertain in economic systems? tomorrows prices future wealth future availability of commodities present and future actions of other people.,Uncertainty is Pervasive,What are rational responses to uncertainty? buying insurance (health, life, auto) a portfolio of contingen。

19、Chapter Six,Demand 需求函数的静态比较分析,What Do We Do in This Chapter?,We conduct comparative statics analysis of ordinary demand functions - the study of how ordinary demands x1*(p1,p2,y) and x2*(p1,p2,y) change as prices p1, p2 and income y change.Theoretically, nothing new.,Own-Price Changes,How does x1*(p1,p2,y) change as p1 changes, holding p2 and y constant? Suppose only p1 increases, from p1 to p1 and then to p1.,x1*(p1),x1*(p1),x1*(p1),p1,x1*(p1),x1*(p1),x1*(p1),。

20、Chapter Seven,Revealed Preference 显现性偏好,What Is the Question of the Chapter?,Suppose we observe a collection of a consumers choices, can we discover his/her preference?Is this possible at all? If so, under what conditions is this possible?(This is the reverse question of finding the optimal choice),Digression: Science vs. Engineering (对比科学家思维与工程师思维）,找问题与解问题的不同 要对问题提问题务虚与务实的不同解释世界与改造世界的不同 旁观者与参与者的不同,Maintained Assumptions on Prefer。