Ch02-DemandandConsumerBehavior.ppt

When the price of a good falls, the impact on the consumer’s choices can be broken down into an income effect and a substitution effect. The income effect is the change in consumption that arises because a lower price makes the consumer better off. The income effect is reflected by the movement from a lower to a higher indifference curve. Summary 小结 当一种物品价格下降时，对消费者选择的影响可以分解为收入效应与替代效应。 收入效应是由于低价格使消费者状况变好而引起的消费变动。 收入效应反映在无差异曲线由低向高的移动上。 The substitution effect is the change in consumption that arises because a price change encourages greater consumption of the good that has become relatively cheaper. The substitution effect is reflected by a movement along an indifference curve to a point with a different slope. Summary 小结 替代效应是由于价格变动鼓励更多消费变得便宜的物品而引起的消费变动。 替代效应表现为沿着一条无差异曲线向不同斜率的点的移动上。 习题 3.下列物品中哪一对可以划分为互补品、替代品和独立品：牛肉、番茄酱、羊肉、香烟、口香糖、猪肉、收音机、电视机、空中旅行、乘公共汽车旅行、出租车和平装书。说明当一种物品的价格上升时，所引起的另一种物品的需求曲线的移动。收入的变动对于空中旅行的需求曲线会发生何种影响？对公共汽车旅行的需求曲线又有何种影响？ 9.供给和需求理论的一个有趣的应用在于：就那些上瘾物品来说，可以对限制其供给的各种方法进行比较。本题假设上瘾物品的需求缺乏价格弹性： A. 一种方法是将其供给拒于国门之外（今天这种方法被用于海洛因和可卡因，在禁酒运动期间，它被用于酒类）。试说明这种方法如何提高了物品的价格，并增加了毒品行业供给者的总收入。 B.另一种可供选择的方法是对这些物品课以重税（今天这种方法被用于烟草和酒类）。运用第4章的税收分析，说明这种方法如何降低毒品业供给者的总收入。 C.试评论上述这两种方法的差异。 3. Substitutes: Beef/lamb/pork, cigarettes/gum, radio/TV/paperbacks, air travel/bus travel. Complements: Beef/ketchup, air and bus travel/taxis. Independent: Goods which consumers perceive as being neither substitutes nor complements. If the price of a good goes up, the demand for its substitutes will increase and the demand for its complements will decrease. An increase in income increases the demand for normal goods and decreases the demand for inferior goods. 9. a. See Figure 5-1 (a). Revenues increase by A and decrease by B. b. See Figure 5-1 (b). Seller revenues fall by the shaded area. c. Limiting supply puts upward pressure on price and may increase revenues to suppliers. Taxes decrease revenues to suppliers. Figure 5-1 * 35 * * * 41 * * 44 * * chapter * * * * * * * * * * * * *