《中级微观经济学》pr8e-ch02ly

* of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. 2.1 Supply and Demand2.2 The Market Mechanism2.3 Changes in Market Equilibrium2.4 Elasticities of Supply and Demand2.5 Short-Run versus Long-Run Elasticities2.6 Understanding and Predicting the Effects of Changing Market Conditions2.7 Effects of Government InterventionPrice ControlsC H A P T E R 2 Prepared by:Fernando Quijano, Illustrator 供应和需求的基础2.1 供应和需求2.2 市场机制2.3 市场均衡的变动2.4 供应和需求的弹性2.5 短期弹性和长期弹性2.6 理解并预测市场状况改变所造成的结果2.7政府干预-价格控制的效应CHAPTER OUTLINE 2 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. 供应与需求2.1供给曲线（ Supply Curve）：在其他影响某商品供给的因素不变的情况下对应于每一给定的价格.生产者所愿意生产的该商品的数量。QS = QS(P | .) 如果生产成本下降、供给曲线向右移动。 3 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. OTHER VARIABLES THAT AFFECT SUPPLY 其他影响因素QS = QS(P | cost, . )供给量还依赖于出价格以外的其他因素，比如，厂商所愿意出售的商品量不但取决于他们所面临的价格，而且还取决于他们的生产成本，这些生产成本包括工资、利率和原材料的成本。当生产成本下降时，不管在哪个价格点，长处都会增加，从而整条供给曲线会右移。经济学家常常用供给的变动来表示供给曲线的移动，而用供给量的变动表示供给曲线上的移动。 4 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. 收人上升，需求曲线向右移动。QD = QD(P)QD = QD(P | income, taste,.)供应与需求2.1需求曲线 5 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. SHIFTING THE DEMAND CURVE收人水平增加 6 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. 替代品 两种商品，当一种商品价格上升会导致另一种商品的需求量增加时，我们称两种商品是替代品。 互补品 两种商品，当一种商品价格上升会导致另一种商品的需求量下降时，我们称两种商品是互补品。 7 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. The Market Mechanism2.2 8 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. When the supply curve shifts to the right, the market clears at a lower price P3 and a larger quantity Q3.FIGURE 2.4Changes in Market Equilibrium市场均衡的变动2.3 9 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. When the demand curve shifts to the right,the market clears at a higher price P3 and a larger quantity Q3.FIGURE 2.5 10 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. SHIFTS IN SUPPLY AND DEMANDFIGURE 2.6 11 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. 弹性 反映了当某自变量上升1%时，因变量将会发生的百分比变化 (2.1)Elasticities of Supply and Demand供给和需求的弹性2.4 PQ QPPP QQE p / 12 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. 线性需求曲线FIGURE 2.11 bPaQ 13 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. 无限弹性 LY: 微斜的比完全平的好理解 14 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. 完全无弹性 LY: 微斜的比完全平的好理解 FIGURE 2.12 15 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. income elasticity of demand OTHER DEMAND ELASTICITIES 其他需求弹性 cross-price elasticity of demand 供给的价格弹性 price elasticity of supply (2.2)(2.3)IQQIII QQEI / mbbmmm bbPQ PQQPPP QQE mb / 16 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. point elasticity of demand （变化无限小） Point versus Arc Elasticities arc elasticity of demand . (2.4)/)(/( : elasticity Arc QPPQE p PQ QPPP QQEp / 17 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. Short-Run versus Long-Run (skipped)LY This section is bad , so far, we assume the world is a point, and adjustment is instantly2.5 18 of 49Copyright 2013 Pearson Education, Inc. Microeconomics Pindyck/Rubinfeld, 8e. EFFECTS OF PRICE CONTROLS.如果没有价格控制，市场在均衡价格P0和均衡数量Q0处出清。如果价格被控制在不得高于Pmax, 则供给降至Q1, 需求升至Q2, 这样就会出现短缺。Effects of Government Intervention 政府干预-价格控制的效应2.7