ManagerialEconomics(2浅色).ppt
2020/10/16,1,Lecture 2 Demand Analysis,Zhang Lei,2020/10/16,2,Topics for Lecture 2,Demand Function Demand Curve Demand, supply and market equilibrium Price elasticity of demand Income elasticity of demand Cross elasticity of demand Demand estimation,Zhang Lei,3,Consumer benefit,一张让你半个月内可以打1场高尔夫球的球票对你有多大价值? 2场的?场的?场的? 收益(价值)曲线 如何保证报告的价值是准确的?,2020/10/16,Zhang Lei,Demand,假定球场只卖半个月内可以打1场高尔夫球的球票(即没有批量销售),但顾客可以选择买票的张数,价格与你愿意购买的球票张数之间的关系为何? 什么价格下你愿意买1张球票?2张?3张?4张?,2020/10/16,4,Zhang Lei,示例,假设B(1) = 800, B(2) = 1400, B(3) = 1800, B(4) = 2000, 而且 p = 550. 该消费者应该购买几张票?,2020/10/16,5,Zhang Lei,Marginal benefit and demand,消费者的目标是什么? 给定价格,消费者的需求为何? 边际收益Marginal benefit The more the less desirable/ diminishing marginal benefit 物以稀为贵/边际收益递减 连续的情况,2020/10/16,6,Zhang Lei,Marginal benefit and demand,需求曲线:描述购买量与价格的关系。 消费者需求由需求曲线来表示 Law of Demand 需求定律:需求量与价格成反比关系。 需求曲线和边际收益曲线:从不同角度看需求曲线,2020/10/16,7,Zhang Lei,D,10,8,6,4,2,1 2 3 4 5,离散的数量The Discrete Case,第一到四张球票对此消费者 的价值分别是8,6,4,2,消费者剩余: 价值超过 价格的部分the value received but not paid for,数量(球票的张数),价格,2020/10/16,8,Zhang Lei,消费者剩余Consumer Surplus:价值超过价格的部分,“I got a great deal!” 我赚了!,2020/10/16,9,Zhang Lei,Price $,Quantity,D,10,8,6,4,2,2 4 6 8 10,消费者成本 16 单位,连续的数量:The Continuous Case,消费者剩余: 32单位,2020/10/16,10,Zhang Lei,2020/10/16,11,Demand Analysis,An important contributor to firm risk arises from sudden shifts in demand for the product or service Demand analysis serves two managerial objectives: (1) it provides the insights necessary for effective management of demand, and (2) it aids in forecasting sales and revenues,Zhang Lei,2020/10/16,12,2.1 Demand Function(需求函数),Markets have two sides those who are selling and those who are buying The behavior of the buyers is summarized in a demand function,Zhang Lei,2020/10/16,13,Need and Demand,Need is infinite Demandthe amount of a good or service that consumers are willing and have the ability to buy in a certain market during a certain period,demand is limited No free lunch !,Zhang Lei,2020/10/16,14,Demand Function,Qd = f ( P, Y, Pr, J, N, A, Pe, ) P Price Y Income level Pr Prices of related goods J Consumers preferences N Population A Advertising expense Pe Expected price of the goods .,Zhang Lei,2020/10/16,15,2.2 Demand Curve(需求曲线),Demand CurveGraph of quantity that buyers will purchase at every possible price of the goods The slope is negative = Law of Demand,Zhang Lei,2020/10/16,16,Individual Demand Curve,The greatest quantity of a good demanded at each price the consumers are Willing to Buy, ceteris paribus,Willing to Buy,Unwilling to Buy,P,Q,Zhang Lei,2020/10/16,17,The horizontal sum of the individual demand curves,The Market Demand Curve,Zhang Lei,2020/10/16,18,The demand curve slopes downward Ceteris paribus (Holding other factors fixed) consumers are usually ready to buy more if the price is lower,Law of Demand (需求规律),Zhang Lei,2020/10/16,19,Change in the Quantity demanded movements along the demand curve: price change Shifts in Demand income level increase etc.,Shifts in Demand,QD,P,D,D,P1,P2,Q1,Q2,Zhang Lei,Price,Quantity,D0,Change in quantity demanded,A to B: 需求量增加,2020/10/16,20,Zhang Lei,Change in demand,tastes 偏好 income 收入 competitive products (substitutes) and their prices 竞争(替代)产品及其价格 complementary products and their prices 互补产品及其价格 政策 policy,2020/10/16,21,Zhang Lei,Demand for Durable Goods耐用品的需求,Expectation about future prices and income 对未来价格和收入的预期 Financing costs 融资成本 Prices of used models 二手货的价格 future value of new good 代表新货物的未来价值 substitute for new good 新旧货物的替代关系,2020/10/16,22,Zhang Lei,2020/10/16,23,2.3 Demand, Supply andMarket Equilibrium(市场均衡),Demand curve Supply curve Market Equilibrium Condition: QS = QD Equilibrium Price Pe ( or Market Clearing Price ) Price that equates the quantity supplied to the quantity demanded Equilibrium Quantity: Qe,Zhang Lei,Factors influencing market demand: 影响市场需求的因素,Income level and distribution 收入高低和分布 Population and demographics 人口多少及构成 Market penetration 市场普及率 Network externality 外部效用,2020/10/16,24,Zhang Lei,2020/10/16,25,P,P2,Pe,P1,E,S,D,Q,Q2,Qe,Q1,Zhang Lei,2020/10/16,26,Supply Function and Supply Curve,QS = g ( P, w, r, Pe, X, ) P Price w Price of labor force r Interest rate (price of capital) Pe Expected price of the good X Tax Relation between the quantity of a good that producers are willing to sell at the price of the good,Zhang Lei,2020/10/16,27,Shift in supply,P,P1,P3,Q1,Q3,Q,S,S,Zhang Lei,2020/10/16,28,Shifts in supply and demand,Shifts in Supply and Demand,P,P2,P1,Q1,Q2,Q,S,D,D,S,Zhang Lei,2020/10/16,29,2.4 Price Elasticity of Demand(需求的价格弹性),Demand depend on Price Price elasticity Consumers income Income elasticity Prices of other goods Cross-price elasticity,Zhang Lei,2020/10/16,30,Elasticity,measures the sensitivity of one variable to another, ceteris paribus! percentage change on one variable resulting from a 1% increase on another,Zhang Lei,2020/10/16,31,Price Elasticity of Demand,Percentage change in quantity demanded of a good resulting from a 1% increase in its price Always be negative,Zhang Lei,2020/10/16,32,Arc Price Elasticity(弧弹性),Arc price elasticity averages over the two points Ex.: Q = 1000 at a price of $10, then Q= 1200 when the price was cut to $6 Solution:,Zhang Lei,2020/10/16,33,Point Price Elasticity (点弹性),Need a demand curve or demand function to find the price elasticity at a point E P = %Q/ %P =(Q/P)(P/Q) If Q = 500 5P, find the point priceelasticity at P = 30; P = 50; and P = 80 EP = (Q/P)(P/Q) = - 5(30/350) = - 0.43 EP = (Q/P)(P/Q) = - 5(50/250) = - 1.0 EP = (Q/P)(P/Q) = - 5(80/100) = - 4.0,Zhang Lei,2020/10/16,34,Price Elastic or Price Inelastic,|EP| 1 price elastic(弹性充足) <1 price inelastic(弹性不足) =1 unit elastic(单位弹性) =0 perfectly inelastic(完全无弹性) = perfectly elastic(完全弹性),D,D,Zhang Lei,2020/10/16,35,Revenue and Price Elasticities,If you raise price, does TR rise? Suppose demand is elastic, and raise price. R = PQ, so, %R = %P+ %Q If elastic, P , but Q a lot Hence R FALLS ! Suppose demand is inelastic, and we decide to raise price. What happens to R and C and profit?,Zhang Lei,2020/10/16,36,Price Elasticity and Business Decisions,According to the relation between price elasticity and revenue, we can get that if demand is price elastic, the firm should cut down the price to get higher revenue if demand is price inelastic, the firm should raise the price to get higher revenue What about the profit?,Zhang Lei,2020/10/16,37,Determinants of the Price Elasticity,The number of close substitutes more substitutes, more elastic The proportion of the budget larger proportion, more elastic The longer the time period permitted more time, generally, more elastic consider examples of business travel versus vacation travel for all three above Empirical results (P.95, Table 3.5),Zhang Lei,2020/10/16,38,Long-Run Elasticity versus Short-Run Elasticity,Some products are more elastic for the long-run than for the short-run , such as gasoline Empirical results in USA: Number of years 1 5 10 20 Price elasticity -0.11 -0.49 -0.82 -1.17 But some products are inelastic for the long-run, such as automobiles,Zhang Lei,2020/10/16,39,2.5 Income Elasticity of Demand(需求的收入弹性),Sensitivity of demand to changes of income,Zhang Lei,2020/10/16,40,Income Elasticity and Characteristics of goods,All Goods,Normal Goods(EY 0) (正常品),Inferior Goods (EY < 0) (低档品),Luxuries(EY 1) (奢侈品),Necessities(EY < 1) (必需品),Zhang Lei,2020/10/16,41,Engel Law (恩格尔定律),Engel(1857), A German Economist: the expenditure on foods of a household depends on its income or total consuming expenditure(From a households survey in Belgium ) Conclusion: As income increases, the share of expenditure on food of a household in total consuming expenditure decreases.,Zhang Lei,2020/10/16,42,Some Empirical Studies,Goods or serviceEyGoods or serviceEy Fuels0.38Telephone1.13 Electricity and Gas0.50Religion and charity1.14 Foods0.51Radio and TV 1.22 Drugs0.61Dinners outdoors1.40 Tobacco0.64Dentistry1.42 Hospital treatment0.69Books1.44 Medical treatment0.75Alcohol1.54 Dress1.02Entertainment1.57 Haircut1.03New Cars2.45 House1.04Domestic Education2.46,Zhang Lei,2020/10/16,43,Income Elasticity and Business Decisions,How to select the direction of corporate development The basic trends of economic development and the change of industrial structure The phases of economic development and the change of industrial structure,Zhang Lei,2020/10/16,44,Zhang Lei,2020/10/16,45,Zhang Lei,2020/10/16,46,Zhang Lei,2020/10/16,47,2.6 Cross-price Elasticity of Demand(交叉价格弹性),Sensitivity of the demanded quantity of one goods to the price of another goods,Zhang Lei,2020/10/16,48,Cross-price Elasticity of Substitutes and Complements,Substitutes have positive cross price elasticities: Butter & Margarine Complements have negative cross price elasticities: VCR machines and the rental price of tapes When the cross price elasticity is zero or insignificant, the products are not related,Zhang Lei,2020/10/16,49,Cross-price Elasticity and Corporate Decisions,Question: Why does GM manufacture cars with five brands(Chevrolet, Pontiac, Buick, Oldsmobile, Cadillac)?,Zhang Lei,2020/10/16,50,2.7 Estimation of Market Demand,Sources of information on demand Survey of market demand Estimation of demand function Some Traps in the Estimation of Demand,Zhang Lei,2020/10/16,51,Sources of information on demand,Consumer Surveys ask a sample of consumers their attitudes Consumer Clinics experimental groups try to emulate a market Market Experiments get demand information by trying different prices Historical Data what happened in the past is guide to the future,Zhang Lei,2020/10/16,52,Survey of Market Demand,Determination of surveyed objectives(or particular market) Choice of the survey variables(what are the possible factors that affect potential consumers?) Determination of survey methods(such as expert consulting, questionnaire analysis based on random sampling. The precision of survey and costs must be considered.),Zhang Lei,2020/10/16,53,Estimation of Demand Function,Statistical analysis(Regression Analysis) An example:IBMs estimation of market demand Income - E Saturation of PC - O Price of IBMs PC - PI Price of competitors PC - PC Q = E O PI PC lnQ = lnE+lnO+lnPI+lnPC,Zhang Lei,2020/10/16,54,Some Traps in the Estimation of Demand,Market demand is not as same as the demand of individual firm Typicality of survey Some different problems maybe exist implicitly in different type of data Do not miss some important factors Estimation results are based on historic data, but corporate decisions are made for the future,Zhang Lei,