Chap-05弹性与其应用(经济学原理-曼昆-中英文双语).pptVIP

Elasticity and Its Application弹性及其应用 Chapter 5 Elasticity . . . 弹性… … is a measure of how much buyers and sellers respond to changes in market conditions. …是衡量买者和卖者对市场条件变动的反应大小的指标。 … allows us to analyze supply and demand with greater precision. …使我们可以更精确地分析供给与需求 Price Elasticity of Demand Price elasticity of demand is the percentage change in quantity demanded given a percent change in the price.  It is a measure of how much the quantity demanded of a good responds to a change in the price of that good. 需求的价格弹性 需求的价格弹性——价格变化1%引起的需求量的变化百分比值。  它是一种物品的需求量对其价格变动的反应程度的衡量。 Determinants of Price Elasticity of Demand需求价格弹性的决定因素 Necessities versus Luxuries 必需品与奢侈品 Availability of Close Substitutes 相近替代品的可获得性 Definition of the Market 市场的定义 Time Horizon 时间的长短 Determinants of Price Elasticity of Demand Demand tends to be more elastic : if the good is a luxury. the longer the time period. the larger the number of close substitutes. the more narrowly defined the market. 价格需求弹性的决定因素 需求倾向于富有弹性： 如果物品是奢侈品 时期更长 相近替代品的数量更多 市场定义的范围更窄 Computing the Price Elasticity of Demand The price elasticity of demand is computed as the percentage change in the quantity demanded divided by the percentage change in price. 计算需求价格弹性 用需求量变动的百分比除以价格变动的百分比来计算需求价格弹性。 Computing the Price Elasticity of Demand 计算需求价格弹性 The Midpoint Method: A Better Way to Calculate Percentage Changes and Elasticities The midpoint formula is preferable when calculating the price elasticity of demand because it gives the same answer regardless of the direction of the change. 中点法:一种计算百分比变化和弹性的更好方法 中点法 是计算需求价格弹性的更好方法，因为无论变动的方向如何，中点法给出了同一个答案。 The Midpoint Method: A Better Way to Calculate Percentage Changes and Elasticities 中点法:一种计算百分比变化和弹性的更好方法 The Variety of Demand Curves Inelastic Demand Quantity demanded does not respond strongly to price changes. Price elasticity of demand is less than one. Elastic Demand Quantity demanded responds strongly to changes in price. Price elasticity of demand is greater