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微观经济学高级版英文原版课件

微观经济学高级版英文原版课件
微观经济学高级版英文原版课件

Chapter1:Key concepts

February19,2013

1Introduction

Economics is the study of choice under scarcity.Typically,consumers want more goods and services than they can a?ord to buy.Similarly,businesses face constraints in terms what funds and resources that they can https://www.sodocs.net/doc/f112225557.html,ernments and countries also face the same type of problem:a government might want to address a large number of social problems,but they have limited resources with which to do so.Economics is about understanding how a party deals with the fact that when they use their resources to pursue one option,they cannot use those resources to do something else.And so,a consumer may have to choose between a new pair of shoes or a textbook,a?rm may have to choose between developing a new product or launching a marketing campaign, and the government may have to choose between improving education or targeting crime.

To understand these issues,economics has developed a set of tools that can be used to analyze these problems.This book provides an introduction to those tools.They can be used to help understand economic problems wherever they arise,be it businesses understanding the markets they compete in,or governments trying to develop social policy,or families trying to manage their households.These tools are not meant to capture everything that is occurring in any given situation.Rather,they are designed to simplify(or to model)a complicated and potentially messy real-world issue into a tractable form that can provide valuable insights.

Given that resources are limited,the key questions that an economy needs to‘decide’are:(a)what to produce;(b)how to produce it;and(c)who should get what is made.In modern economies,the answers to these questions are largely determined by the market –that is,by the interaction of sellers and buyers in the market.1Sometimes,however, the government also helps determine the answer to these questions,by regulating or intervening in the market.Consequently,our focus in this microeconomics text will be on the study of individuals(consumers,?rms,and governments)and their interaction in markets.

This chapter provides a few key concepts that underpin the analysis in the rest of the book,as well as economics analysis in general.

1By‘market’,we simply mean a place where buyers and sellers of a particular good or service meet, such as a traditional bazaar or an online trading site.

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2Scarcity and opportunity cost

As noted above,it is usually the case that resources are limited,so that not all wants can be met.We call this situation scarcity.

Scarcity also means that individuals,businesses and societies face tradeo?s;by choos-ing one thing,a person must give up or miss out on another thing.For example,if a consumer uses their money to buy product X,they cannot then use that same money to buy something else.2We use the concept of opportunity cost to measure that tradeo?. Thus,the opportunity cost of any choice is the value of the best forgone alternative. In the example above,if the consumer buys product X,and the next best thing they could have done is buy product Y,the opportunity cost of buying X is forgoing Y.

Individuals also face opportunity costs in terms of their time–that is,if a person spends his time doing one thing,he cannot also spend that time doing another.

Example.Suppose Andrew prefers to spend his Saturday afternoon walk-

ing.The next best thing that he could have done is to sleep,and his third

best choice is to go swimming.Therefore,if Andrew goes for a walk,the op-

portunity cost of going for a walk is not sleeping,as this is his best foregone

opportunity.The option of swimming is not relevant here because it is not

the next best opportunity.

Opportunity costs include both explicit costs and implicit costs.Explicit costs are costs that involve direct payment(or,in other words,would be considered as costs by an accountant).Implicit costs are opportunities that are forgone,but do not involve an explicit cost.3

Example.Suppose Stephen decides to go to university,and his next best

option is to work at a construction site and earn$80K over the year.The

explicit costs are those that Stephen must directly pay to go to university,

such as student fees,the cost of textbooks,and so on.The implicit costs

are the opportunities that Stephen must forgo–that is,working at the

construction site and earning$80K.

It is important to note that opportunity cost only includes costs that could change if a di?erent decision were made.Opportunity cost does not include sunk(or unrecoverable) costs.Sunk costs are costs that have been incurred and cannot be recovered no matter what.For example,if Katrien spends the weekend reading an accounting textbook, no matter what she does(such as whether or not she decides to continue studying accounting),she cannot get that time back.Similarly,if a business spent$100K on an advertising campaign last year,regardless of what they decide to do this year,that money(and e?ort)cannot be recovered.

2It is common to hear people refer to the‘economics’of a particular thing.This colloquial statement really means that,given the limited resource available,a choice had to be made and something(possibly worthwhile)could not be done.

3Sometimes,economists distinguish between‘economic costs’and‘accounting costs’.Economic costs is just another term for opportunity costs,and therefore includes explicit and implicit costs. Accounting costs refers to explicit costs only.

2

3Marginal analysis

Typically,we assume that economic agents are rational and act to maximize their bene?ts from their economic transactions.4For example,consumers seek to maximize their bene?ts from consumption and?rms seek to maximize their pro?ts from production. One way that economic agents can solve this maximization problem is by considering the additional bene?t or additional cost of any action.This sort of analysis is referred to as marginal analysis and it is a recurring theme both in this book and economics generally.

For instance,consider a consumer faced with the decision of whether to buy one more unit of a particular good.That consumer might consider the extra bene?t he derives from buying that extra unit;this is referred to as the marginal bene?t of that extra unit of the good.The consumer might also consider the additional cost of buying one more unit;this is referred to as the marginal cost of purchasing another unit,which is typically the price of the good.In making their?nal decision,the consumer will weigh the marginal bene?t against the marginal cost of buying that extra unit.For example, if a consumer is considering buying another cup of co?ee,and the marginal bene?t is$5 and the marginal cost is$3,the consumer will be better o?by buying the extra co?ee.

Each of the marginal terms noted above,and many others,will be discussed at length throughout the book.What is crucial to note is that the term‘marginal’simply means means additional or extra.That is,we interested to see what happens if we increase things(such as the number of co?ees bought)by a small amount.

4Ceteris paribus

The notion of ceteris paribus is also an important foundation of economic analysis.As noted,because the real world is often complicated and messy,it is often necessary to simplify real-world situations into tractable economic models,in order to better analyze them.Thus,in order to determine the e?ect of a particular thing,economists tend to examine the impact of one change at a time,holding everything else constant.This is often called ceteris paribus,which roughly means‘other things equal’.

For instance,suppose we are interested in how a change in price will a?ect the quantity demanded of a good.However,in reality,demand for a good can be a?ected by a number of other factors,such as changes in the tastes or income of consumers,or the availability or price of substitute goods.Therefore,in order to isolate the e?ect of price upon quantity demanded,we need hold everything else constant.This is not to deny that in the real world multiple changes can occur at a time–they often do.Rather, to fully understand the relationship between price and demand,it is essential to isolate that relationship from other events that might also be occurring.For example,a?rm 4We are not suggesting that,in the real word,consumers are always fully rational or that?rms do not sometimes have other objectives.Rather,we adopt this simplifying assumption because it allows us to analyze the behaviour of economic agents in markets.Such analysis will be fairly accurate,provided that on average individual consumers and?rms act more or less in their own interest.

3

might be interested in the e?ect of advertising on demand for its product.To understand the impact of advertising,it is crucial to remove other factors that could a?ect demand, otherwise advertising could be attributed too much(or too little)in?uence,which could lead to poor decision-making by the?rm regarding its next advertising campaign.

5Correlation and causation

Another factor to keep in mind is the di?erence between correlation and causation. Correlation refers to a situation in which two or more things are observed to move together(or against each other).On the other hand,causation refers to a situation where changes in one thing brings about or causes change in another thing.To make statements about causation requires an economic theory about how the world works, rather than just observing a statistical relationship between several variables.

Sometimes,when we observe correlation between two variables,A and B,it is because one causes the other.Sometimes,it is because a third factor causes changes in A and B(like a rising tide causing two boats to rise in their moorings).Sometimes,there is no connection between the two variables and it is just by chance that we observed the change in both variables at the same time.Without a theory about how a change in one variable a?ects the other,it is not possible to say which is the case.

4

微观经济学中各个字母缩写对应的中英文意思教案资料

微观经济学中各个字母缩写对应的中英文 意思

P:价格Price Q:数量Number D:需求Demand S供给Supply E:均衡(或期望)Equilibrium 效用Utility TU:Total utility总效用 MU:Marginal utility边际效用 CS: Consumer surplus消费者剩余 MRS:商品的边际替代率Marginal rate of substitution L:劳动力Labor TP:总产量 AP:平均产量 MP:边际产量 MRTS:边际技术替代率 STC:短期总成本土地( Land)成本(Capital) 边际效用( Marginal utility)利润(Profit)长期(Long run)TFC:总不变成本Total fixed cost TVC:总可变成本Total variable cost TC:总成本Total cost AFC:平均不变成本Average fixed cost AVC:平均可变成本Average variable cost) AC:平均总成本Average total cost 平均成本(Average cost) MC:边际成本Marginal cost LTC:长期总成本Long run total cost LAC:长期平均成本Long run average cost SAC:短期平均成本Short run average cost LMC:长期边际成本Long run marginal cost SMC:短期边际成本Short run marginal cost TR:总收益Total revenue AR:平均收益Average revenue MR:边际收益Marginal revenue

最新版微观经济学精品习题英文版 (with answer) (16)

Chapter 17 Monopolistic Competition 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. _ __. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. _ __. 1. Because monopolistically competitive firms produce differentiated products, each firm ( d ) a.faces a demand curve that is horizontal. b.faces a demand curve that is vertical. c.has no control over product price. d.has some control over product pric e. 2. Which of the following conditions distinguishes monopolistic competition from perfect competition? ( d ) a. Number of sellers. b. Freedom of entry and exit. c. Small size firms. d. Differentiation of product. 3. A firm in a monopolistically competitive market is similar to a monopolist in the sense that it ( b ) a.must overcome significant barriers to entry. b.faces a downward-sloping demand curve. c.there are no barriers to entry or exit. d.there is only one seller of the good. 4. If existing firms in the fast-food market, which is a monopolistically competitive market, realize sizable economic profits in the short run, the demand of existing firms will ( a ) a.decrease and become more elastic. b.decrease and become less elasti c. c.increase and become more elastic. d.increase and become less elastic.

平新乔《微观经济学十八讲》课后习题详解(策略性博弈与纳什均衡)

第10讲 策略性博弈与纳什均衡 1.假设厂商A 与厂商B 的平均成本与边际成本都是常数,10A MC =,8B MC =,对厂商产出的需求函数是 50020D Q p =- (1)如果厂商进行Bertrand 竞争,在纳什均衡下的市场价格是多少? (2)每个厂商的利润分别为多少? (3)这个均衡是帕累托有效吗? 解:(1)如果厂商进行Bertrand 竞争,纳什均衡下的市场价格是10B p ε=-,10A p =,其中ε是一个极小的正数。理由如下: 假设均衡时厂商A 和B 对产品的定价分别为A p 和B p ,那么必有10A p ≥,8B p ≥,即厂商的价格一定要高于产品的平均成本。其次,达到均衡时,A p 和B p 都不会严格大于10。否则,价格高的厂商只需要把自己的价格降得比对手略低,它就可以获得整个市场,从而提高自己的利润。所以均衡价格一定满足10A p ≤,10B p ≤。但是由于A p 的下限也是10,所以均衡时10A p =。给定10A p =,厂商B 的最优选择是令10B p ε=-,这里ε是一个介于0到2之间的正数,这时厂商B 可以获得整个市场的消费者。综上可知,均衡时的价格为10A p =,10B p ε=-。 (2)由于厂商A 的价格严格高于厂商B 的价格,所以厂商A 的销售量为零,从而利润也是零。下面来确定厂商B 的销售量,此时厂商B 是市场上的垄断者,它的利润最大化问题为: max pq cq ε>- ①

其中10p ε=-,()5002010q ε=-?-,把这两个式子代入①式中,得到: ()()0 max 1085002010εεε>----???? 解得0ε=,由于ε必须严格大于零,这就意味着ε可以取一个任意小的正数,所以厂商B 的利润为: ()()500201010εε-?--????。 (3)这个结果不是帕累托有效的。因为厂商B 的产品的价格高于它的边际成本,所以如果厂商B 和消费者可以为额外1单位的产品协商一个介于8到10ε-之间的价格,那么厂商B 的利润和消费者的剩余就都可以得到提高,同时又不损害厂商A 的剩余(因为A 的利润还是零)。 2.(单项选择)在下面的支付矩阵(表10-1)中,第一个数表示A 的支付水平,第二个数表示B 的支付水平,a 、b 、c 、d 是正的常数。如果A 选择“下”而B 选择“右”,那么: 表10-1 博弈的支付矩阵 (1)1b >且1d < (2)1c <且1b < (3)1b <且c d < (4)b c <且1d < (5)1a <且b d <

微观经济学名词解释和中英文对照

【经济人】 从事经济活动的人所采取的经济行为都是力图以自己的最小经济代价去获得自己的最大经济利益。 【需求】 消费者在一定时期内在各种可能的价格水平愿意而且能够购买的该商品的数量。 【供给】 生产者在一定时期内在各种价格水平下愿意并且能够提供出售的该种商品的数量。 【均衡价格】。 一种商品的均衡价格是指该种商品的市场需求量和市场供给量相等时的价格。 【供求定理】。 其他条件不变的情况下,需求变动分别引起均衡价格和均衡数量的同方向的变动,供给变动引起均衡价格的反方向变动,引起均衡数量的同方向变动。 【经济模型】。 经济模型是指用来描述所研究的经济事物的有关经济变量之间相关关系的理论结构。 【弹性】 当一个经济变量发生1%的变动时,由它引起的另一个经济变量变动的百分比。 【弧弹性】 表示某商品需求曲线上两点之间的需求量的变动对于价格的变动的反应程度。 【点弹性】 表示需求曲线上某一点上的需求量变动对于价格变动的反应程度。 【需求的价格弹性】 表示在一定时期内一种商品的需求量变动对于该商品的价格变动的反应程度。或者说,表示在一定时期内当一种商品的价格变化百分之一时所引起的该商品的需求量变化的百分比。【需求的交叉价格弹性】。 表示在一定时期内一种商品的需求量的变动相对于它的相关商品的价格变动的反应程度。或者说,表示在一定时期内当一种商品的价格变化百分之一时所引起的另一种商品的需求量变化百分比。 【替代品】 如果两种商品之间能够相互替代以满足消费者的某一种欲望,则称这两种商品之间存在着替代关系,这两种商品互为替代品。 【需求的收入弹性】 需求的收入弹性表示在一定时期内消费者对某种商品的需求量变动对于消费者收入量变动的反应程度。或者说,表示在一定时期内当消费者的收入变化百分之一时所引起的商品需求量变化的百分比。 【恩格尔定律】。 在一个家庭或在一个国家中,食物支出在收入中所占的比例随着收入的增加而减少。用弹性的概念来表述它则可以是:对于一个家庭或一个国家来说,富裕程度越高,则食物支出的收入弹性就越小;反之,则越大。 【总效用和边际效用】 总效用是指消费者在一定时间内从一定数量的商品的消费中所得到的效用量的总和。边际效用是指消费者在一定时间内增加一单位商品的消费所得到的效用量的增量。 【边际效用递减规律】 在一定时间内,在其他商品的消费数量保持不变的情况下,随着消费者对某种商品消费的增

平新乔《微观经济学十八讲》课后习题详解(VNM效用函数与风险升水)【圣才出品】

第4讲 VNM 效用函数与风险升水 1.(单项选择)一个消费者的效用函数为()bw u w ae c -=-+,则他的绝对风险规避系数为: (A )a (B )a b + (C )b (D )c 【答案】C 【解析】由消费者的效用函数()bw u w ae c -=-+,可得()bw u'w abe -=,()2bw u w ab e -''=-, 则可得该消费者的风险规避系数为:()()()2bw a bw ab e R w u w w b abe ---=-"'=-=。 2.证明:若一个人的绝对风险规避系数为常数c ,则其效用函数形式必为()cw u w e -=-,这里w 代表财产水平。 证明:这是一个求积分的问题,即由绝对风险规避系数来倒求效用函数。根据绝对风险规避系数的定义,就有: ()()() a u w R w c u w "=- =' 对等式(1)最后一个等号两边积分得: () () d d u w w c w u w "=-? ?' 即:()ln u w cw C '=-+。 进一步整理得: ()cw C cw u w e Ce -+-'== ① 其中0C C e =>,对①式两边积分得:

()1cw C u w e C c -=- + 其中1C 为任意实数。根据效用函数的单调递增特性可知0c >(因为如果0c <,就说明财富越少,消费者的效用就越高,这不符合正常的情况)。又因为效用函数的单调变换不改变它所代表的偏好,所以()1cw C u w e C c -=- +表示的偏好也可以用()cw u w e -=-表示。 3.若一个人的效用函数为2u w aw =-,证明:其绝对风险规避系数是财富的严格增函数。 证明:由效用函数()2u w w aw =-,可得()12u'w w α=-,()2u w α''=-,则该消费者的绝对风险规避系数为: ()()() 212a u w R w u w w α α"=- = '- 其中12w α≠ 。因此,当12w α ≠时: ()() () 2 2 d 20d 12a R w w w αα= >- 即绝对风险规避系数是财富的严格增函数。 4.设一种彩票赢得900元的概率为0.2,而获得100元的概率为0.8。计算该彩票的期望收入。若一个人对该彩票的出价超过彩票的期望收入,请写出这个人的效用函数形式。(形式不唯一)。 答:(1)用w 表示风险收入,那么该风险收入的期望值为: ()0.29000.8100260E w =?+?=(元) (2)如果此人对该彩票的出价超过彩票的期望收入,说明他是风险喜好者(如图4-1所示)。一个可能的效用函数是2u w =。

平新乔《微观经济学十八讲》课后习题详解(第2讲 间接效用函数与支出函数)

平新乔《微观经济学十八讲》第2讲 间接效用函数与支出函数 跨考网独家整理最全经济学考研真题,经济学考研课后习题解析资料库,您可以在这里查阅历年经济学考研真题,经济学考研课后习题,经济学考研参考书等内容,更有跨考考研历年辅导的经济学学哥学姐的经济学考研经验,从前辈中获得的经验对初学者来说是宝贵的财富,这或许能帮你少走弯路,躲开一些陷阱。 以下内容为跨考网独家整理,如您还需更多考研资料,可选择经济学一对一在线咨询进行咨询。 1.设一个消费者的直接效用函数为12ln u q q α=+。求该消费者的间接效用函数。并且运用罗尔恒等式去计算其关于两种物品的需求函数。并验证:这样得到的需求函数与从直接效用函数推得的需求函数是相同的。 解:(1)①当20y p α->时,消费者的效用最大化问题为: 12 12 2,112m ln ax q q s t q p p y q q q α..+=+ 构造拉格朗日函数: ()121122ln L q q q y p p q αλ--=++ L 对1q 、2q 和λ分别求偏导得: 111 0L p q q α λ?=-=? ① 22 10L p q λ?=-=? ② 11220q L y p p q λ ?=--=? ③ 从①式和②式中消去λ后得: 2 11 p q p α*= ④ 再把④式代入③式中得: 2 2 2y p p q α*-= ⑤ 从而解得马歇尔需求函数为: 2 11 p q p α*= 2 2 2 y p p q α*-= 由⑤式可知:当20y p α->时,2 0q * >,消费者同时消费商品1和商品2。 将商品1和商品2的马歇尔需求函数代入效用函数中得到间接效用函数: ()()21 12122 ,,,ln p v p p y p q q y u p ααα** =+-= ②当20y p α-≤时,消费者只消费商品1,为角点解的情况。 从而解得马歇尔需求函数为:

平新乔《微观经济学十八讲》课后习题详解(第10讲 策略性博弈与纳什均衡)

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平新乔《微观经济学十八讲》模拟试题及详解【圣才出品】

平新乔《微观经济学十八讲》配套模拟试题及详解(一) 一、简答题(每题10分,共40分) 1.假设政府与流浪者之间存在如下社会福利博弈: 请分析下,在这场博弈中政府和流浪汉各自有没有优势策略均衡?有没有纳什均衡?在此基础上说明优势策略均衡和纳什均衡的区别和联系。 答:(1)从流浪汉的角度来看,如果政府选择“救济”,流浪汉的最佳策略是“游手好闲”;如果政府选择“不救济”,流浪汉的最佳策略是“寻找工作”。因此,流浪汉没有优势策略。从政府的角度来看,如果流浪汉选择“寻找工作”,政府的最佳策略是“救济”;如果流浪汉选择“游手好闲”,政府的最佳策略是“不救济”。因此,政府也没有优势策略。从而,这场博弈中没有优势策略均衡。如果流浪汉选择“寻找工作”,则政府会选择“救济”;反过来,如果政府选择“救济”,则流浪汉会选择“游手好闲”。因此,(救济,寻找工作)不是纳什均衡,同理,可以推断出其他三个策略组合也不是纳什均衡。所以,这场博弈中也没有纳什均衡。 (2)当博弈的所有参与者都不想改换策略时所达到的稳定状态称为均衡。无论其他参与者采取什么策略,该参与者的唯一最优策略就是他的优势策略。由博弈中所有参与者的优势策略所组成的均衡就是优势策略均衡。给定其他参与者策略条件下每个参与者所选择的最优策略所构成的策略组合则是纳什均衡。 优势策略均衡与纳什均衡的关系可以概括为:优势策略均衡一定是纳什均衡,纳什均衡

不一定是优势策略均衡。 2.(1)张大山的偏好关系的无差异曲线由下列函数形式表达 (为常数) 其偏好满足严格凸性吗?为什么? (2)李经理的偏好关系的无差异曲线由下列函数表达: 该偏好满足单调性吗?满足凸性吗?满足严格凸性吗?为什么? (3)崔大牛的偏好关系的无差异曲线由下列函数表达: 该偏好满足单调性吗?满足凸性吗?为什么?你能从生活中举出一个例子对应这种偏好关系吗? 答:(1)该偏好满足严格凸性,理由如下: 无差异曲线的图像如图1所示,可知其偏好满足严格凸性。 图1 无差异曲线 将无差异曲线转化为,则有:

平新乔《微观经济学十八讲》课后习题(第9~12讲)【圣才出品】

平新乔《微观经济学十八讲》课后习题 第9讲古诺(Cournot)均衡、Bertrand 与不完全竞争 1.考虑一个由两家企业组成的寡头垄断行业,市场的需求由10p Q =-给出。这两家企业的成本函数分别为 1142C Q =+,2233C Q =+。 (1)若两家企业串通追求共同的利润最大化,总的产量水平是多少?市场价格为多少?各自生产多少?各自利润多大? (2)若两家企业追求各自的利润最大化,利用古诺模型,各自生产多少?各自利润多大?市场价格多大?并给出各自的反应函数。 (3)若串通是非法的,但收购不违法。企业1会出多少钱收购企业2? 解:(1)若两家企业串通时,它们的目标是追求总利润的最大化,则总利润函数为: ()()()221211221112228277 p Q Q C Q C Q Q Q Q Q Q Q π=+--=-+--+-利润最大化的一阶条件为: 121 2820Q Q Q π?=-+-=?212 2720Q Q Q π?=-+-=?上述两式无解,说明两家企业串通后只由一家企业生产,不存在两家企业同时生产的情况。 根据两家企业的成本函数可得12MC =,23MC =。由于两家企业的边际成本为常数,且企业1的边际成本小于企业2的边际成本,所以串通后所有的产量全部由企业1提供,故20Q =。则总利润函数变为:

21187 Q Q π=-+-利润最大化的一阶条件为:11 d 280d Q Q π=-+=,解得14Q =。因此两家企业串通后,总的产量水平为124Q Q Q =+=; 市场价格为106p Q =-=; 企业1的利润为21118412Q Q π=-+-=;企业2的利润为13π=-。 (2)由已知可得企业1的利润函数为: ()()211112184 pQ C Q Q Q Q π=-=-+--利润最大化的一阶条件为:121 280Q Q Q π?=-+-=?,得企业1的反应函数为:12 40.5Q Q =-类似的方法可以得到企业2的反应函数为: 21 3.50.5Q Q =-联立两企业的反应函数可以解得古诺均衡时每家企业的产量为:13c Q =,22c Q =。此时市场价格为105p Q =-=,两企业的利润分别为15π=,21π=。 (3)企业1对企业2的收购价格不会高于两种情况下的利润差,即1257p ≤-=。 2.一个垄断企业的平均成本和边际成本为5AC MC ==,市场的需求曲线函数为53Q p =-。 (1)计算这个垄断企业利润最大化时的产量和市场价格,以及其最大化的利润。 (2)若又有第二个企业加入该市场,市场的需求不变。第二个企业生产成本和第一个企业相同,在古诺模型下,求各企业的反应曲线、市场价格、各企业的产量和利润。 (3)若有N 个企业加入该市场,市场的需求不变。这N 个企业生产成本和第一个企业都相同,在古诺模型下,求市场价格、各企业的产量和利润。

微观经济学十八讲思维导图

微观经济学十八讲思维导图 1.1马歇尔需求函数: .................................................................................................................... 1 1.2间接效用函数: ........................................................................................................................ 1 1.3支出函数: ................................................................................................................................ 1 1.4希克斯需求函数: .................................................................................................................... 2 1.5关于间接效用函数的性质 ........................................................................................................ 2 1.6谢泼特引理 ................................................................................................................................ 3 1.7 Cobb-Douglas 效用函数中指数的经济含义。 ...................................................................... 4 1.8斯拉茨基公式 ............................................................................................................................ 5 1.9 四个重要函数之间的关系 ....................................................................................................... 6 1.10 关于斯拉茨基补偿与希克斯补偿的计算 .. (6) 第一讲:需求理论 1.1马歇尔需求函数: 是对效用函数1,2()u x x ,在约束条件1122p x p x y +=下求极值(最优消费量),得到1,2x x 的值。(给定的价格与收入,消费者为了让效用最大而选择对x 的需求量。) 1.2间接效用函数: 由于最优消费量对应的是最大化的效用,所以,在最大化的效用,1,2max ()n x R u x x + ∈与(,)p y 之间存在函数关系。 ..1,2max ()(,)n s t x R u x x p y p x y + ∈= ?≤ 1.3支出函数: 当消费者面临的价格给定时,为了达到给定的效用水平,如何花钱最省?这个问题不用考虑你有多少收入,问的只是:为了达到某一特定的效用水平,你该花多少钱?

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