供给与需求的市场力量 The Market Forces of 供给与需求的 Supply and Demand 市场力量 ◆供给与雳求是经济学家最常用的两个术语 The Market Forces of Supply and demand are the two words that Supply and demand ◆供给与求是推动市场经济运转的力量所在 Supply and demand are the forces that make market economies work 第4章 ◆现代微观经济学研究供给、需求和市场均 Chapter 4 Modern microeconomics is about supply, demand, and market equilibrium. 市场 市场 Markets Markets ◆买方决定需求 个市场就是由某种商品或服务的买者和 Buvers determine demand. 卖者组成的群体 A market is a group of buyers and sellers of a particular good or service. ◆术语供给和需求指人们的行为…当他们 在市场中相互作用时。 The terms supply and demand refer to the behavior of people. as they interact with ◆卖方决定供给。 one another in markets Sellers determine supply 市场类型:竞争市场 竞争:完全竞争与否 Market Type: Competition A Competitive Market Perfect and otherwise 竞争性市场是这样一个市场 完全竞争 Perfect Competition A competitive market is a market ◆物品完全相同。 拥有众多买者和者 Products are the same ith many buyers and sellers. ◆买者、卖者如此众多以至于个人无法对价格施 不受住何一个人肌 加影响 Numerous buyers and sellers so that each has no 买者和着所的价搭被的在小的落内 influence over price in which a narrow range of prices are established that buyers and sellers act upon ◆买者、卖者都是价格接收者。 Buyers and Sellers are price takers
1 1 第4章 Chapter 4 供给与需求的 市场力量 The Market Forces of Supply and Demand 2 供给与需求的市场力量 The Market Forces of Supply and Demand 供给与需求是经济学家最常用的两个术语。 Supply and demand are the two words that economists use most often. 供给与需求是推动市场经济运转的力量所在。 Supply and demand are the forces that make market economies work. 现代微观经济学研究供给、需求和市场均衡。 Modern microeconomics is about supply, demand, and market equilibrium. 3 市场 Markets 一个市场就是由某种商品或服务的买者和 卖者组成的群体。 A market is a group of buyers and sellers of a particular good or service. 术语供给和需求指人们的行为……当他们 在市场中相互作用时。 The terms supply and demand refer to the behavior of people . . . as they interact with one another in markets. 4 市场 Markets 买方决定需求。 Buyers determine demand. 卖方决定供给。 Sellers determine supply. 5 市场类型：竞争市场 Market Type: A Competitive Market 竞争性市场是这样一个市场…… A competitive market is a market. . . ……拥有众多买者和卖者 with many buyers and sellers. ……不受任何一个人操纵 that is not controlled by any one person. ……买者和卖者所遵循的价格被约束在窄小的范围内。 in which a narrow range of prices are established that buyers and sellers act upon. 6 竞争：完全竞争与否 Competition: Perfect and Otherwise 物品完全相同。 Products are the same 买者、卖者如此众多以至于个人无法对价格施 加影响。 Numerous buyers and sellers so that each has no influence over price 买者、卖者都是价格接收者。 Buyers and Sellers are price takers 完全竞争Perfect Competition
竞争:完全竞争与否 竞争:完全竞争与否 Competition: Competition Perfect and Otherwise Perfect and otherwise ◆垄断 Monopoly ◆新党争 Monopolistic Competition ◆只有一个卖者,它控制价格 ◆萨多音 One seller, and seller controls price Many sellers ◆寡头 Oligopoly ●微小差产品 ◆少数几个卖者 Few sellers Slightly differentiated products ●每个卖粼就为自已的产品定薺 Each seller may set price for its own product 需求 需求的决定 Demand Determinants of demand 需求量是买者愿意而且能够购买的 ◆市场价格 Market price 商品数量 ◆消费者收入 Consumer income Quantity demanded ◆相关商品的价格 is the amount Prices of related goods of a good that buyers are ◆嗜好 Tastes willing and able to purchase ◆预期 Expectations 需求定律 需求表 Law of demand Demand schedule 求定律:价格与需求量负相关。 求表显示了商品价格与需求量之间 The law of demand states that there 的关系 is an inverse relationship between The demand schedule is a table price and quantity demanded. that shows the relationship between the price of the good and the quantity demanded
2 7 竞争：完全竞争与否 Competition: Perfect and Otherwise 垄断 Monopoly 只有一个卖者，它控制价格 One seller, and seller controls price 寡头 Oligopoly 少数几个卖者 Few sellers 8 竞争：完全竞争与否 Competition: Perfect and Otherwise 垄断竞争 Monopolistic Competition 许多卖者 Many sellers Many sellers 存在微小差别的产品 Slightly differentiated products Slightly differentiated products 每个卖者都能为自己的产品设定价格 Each seller may set price for its own product Each seller may set price for its own product 9 需求 Demand 需求量是买者愿意而且能够购买的 商品数量。 Quantity demanded is the amount of a good that buyers are willing and able to purchase. 10 需求的决定 Determinants of Demand 市场价格 Market price 消费者收入 Consumer income 相关商品的价格 Prices of related goods 嗜好 Tastes 预期 Expectations 11 需求定律 Law of Demand 需求定律：价格与需求量负相关。 The law of demand states that there is an inverse relationship between price and quantity demanded. 12 需求表 Demand Schedule 需求表显示了商品价格与需求量之间 的关系。 The demand schedule is a table that shows the relationship between the price of the good and the quantity demanded
需求表 需求曲线 Demand schedule Demand curve 格数量 Price Quantity 需求曲线:是将价格与需求量相联系的向 右下方倾斜的曲线。 $0.00 12 The demand curve is the downward- sloping line relating price to quantity 1.00 demanded 1.50 2.00 2.50 186420 需求曲线 “其他条件不变” 命的格 Demand curve Ceteris Paribus 53.00 价格 被研究的诸变量之外,其余所有变量均假定为恒 Price Quantity 定。字面意义是“其他条件不变(相同)”。 Ceteris paribus is a Latin phrase that means all variables other than the ones being studied are assumed to be constant. Literally, ceteris paribus 需求曲线向下倾斜是因为,在其他条件不变 的情况下,较低的价格意味着较大的需求量 The demand curve slopes downward because, ceteris paribus, lower prices 01 2345678910 11 12 Quantity of Ices imply a greater quantity demanded! 市场需求 需求的变化与需求量的变化 Market Demand Change in Quantity Demanded versus change in Demand 嘉棗指的所有个人对某种商品或劳务的 market demand refers to the sum of al 签求量的变化 ndividual demands for a particular good or service Change in Quantity Demanded 形青录曲盒人需求曲线否式平加总便得 ◆沿着需求曲线的移动。 Movement along the demand curve. Graphically, individual demand curves are ◆由该产品价的变动所引起 ummed horizontally to obtain the market Caused by a change in the price of the product. demand curve
3 13 需求表 Demand Schedule 价格 Price 数量 Quantity $0.00 12 0.50 10 1.00 8 1.50 6 2.00 4 2.50 2 3.00 0 14 需求曲线 Demand Curve 需求曲线：是将价格与需求量相联系的向 右下方倾斜的曲线。 The demand curve is the downwardsloping line relating price to quantity demanded. 15 需求曲线 Demand Curve $3.00 2.50 2.00 1.50 1.00 0.50 1 3 4 5 6 7 8 9 10 12 2 11 冰激凌蛋卷的价格 Price of IceCream Cone 冰激凌蛋卷的需求数量 Quantity of IceCream Cones 0 价格 Price 数量 Quantity $0.00 12 0.50 10 1.00 8 1.50 6 2.00 4 2.50 2 3.00 0 16 “其他条件不变” Ceteris Paribus Ceteris paribus 是一个拉丁习惯用语，意思是除了 被研究的诸变量之外，其余所有变量均假定为恒 定。字面意义是“其他条件不变（相同）”。 Ceteris paribus is a Latin phrase that means all variables other than the ones being studied are assumed to be constant. Literally, ceteris paribus means “other things being equal.” 需求曲线向下倾斜是因为，在其他条件不变 的情况下，较低的价格意味着较大的需求量 The demand curve slopes downward because, ceteris paribus, lower prices imply a greater quantity demanded! 17 市场需求 Market Demand 市场需求指的是所有个人对某种商品或劳务的 需求总和。 Market demand refers to the sum of all individual demands for a particular good or service. 从图形上看，个人需求曲线在水平上加总便得 到市场需求曲线。 Graphically, individual demand curves are summed horizontally to obtain the market demand curve. 18 需求的变化与需求量的变化 Change in Quantity Demanded versus Change in Demand 需求量的变化 Change in Quantity Demanded 沿着需求曲线的移动。 Movement along the demand curve. 由该产品价格的变动所引起。 Caused by a change in the price of the product
需求量的变动 Changes in Quantity 需求量变化与需求变化 邻包香 Demanded Change in Quantity Demanded 高了香烟价格,引录 versus Change in Demand 动。 A tax that raises the price of cigarettes 需求变化 Change in demand along the demand curve. ◆需求曲线发生移动,要么左移,要么右移 A shift in the demand curve, either to the left or right. 2.00 ◆由该物品价格之外的其他决定因素引起。 Caused by a change in a determinant other than he price 需求的变化 Changes in Demand 消费者收入 Consumer Income Cone 随着收入的增加,对正常品的需求会增 As income increases the demand for a normal good will increase. 家 ◆随着收入的增加,对劣等品(低档品) 的需求会减少。 D2 As income increases the demand for an D fe d will de 消费者收入:正常品 消费者收入:劣等品 Consumer Income: Normal Good Consumer Income: Inferior Good An increase 2.50 收入增加 Increa 求减少 An increase 1.00 0123456789101112 012345678910112 Quantity o
4 19 需求量的变动 Changes in Quantity Demanded 0 D1 每包香烟 的价格 Price of Cigarettes per Pack 每天抽烟的数量 Number of Cigarettes Smoked per Day 税收抬高了香烟价格，引致 了需求量由A到C沿着需求曲 线运动。 A tax that raises the price of cigarettes results in a movement along the demand curve. A C 20 2.00 $4.00 12 20 需求量变化与需求变化 Change in Quantity Demanded versus Change in Demand 需求变化 Change in Demand 需求曲线发生移动，要么左移，要么右移 A shift in the demand curve, either to the left or right. 由该物品价格之外的其他决定因素引起。 Caused by a change in a determinant other than the price. 21 需求的变化 Changes in Demand 0 D1 价格 Price of Ice-Cream Cone 数量 Quantity of Ice-Cream Cones D3 D2 需求增加 Increase in demand 需求减少 Decrease in demand 22 消费者收入 Consumer Income 随着收入的增加，对正常品的需求会增 加。 As income increases the demand for a normal good will increase. 随着收入的增加，对劣等品（低档品） 的需求会减少。 As income increases the demand for an inferior good will decrease. 23 消费者收入：正常品 Consumer Income：Normal Good $3.00 2.50 2.00 1.50 1.00 0.50 1 3 4 5 6 7 8 9 10 12 2 11 Price of Ice-Cream Cone Quantity of Ice-Cream Cones 0 需求增加 Increase in demand 收入增加… An increase in income... D1 D2 24 消费者收入：劣等品 Consumer Income：Inferior Good $3.00 2.50 2.00 1.50 1.00 0.50 1 3 4 5 6 7 8 9 10 12 2 11 Price of Ice-Cream Cone Quantity of Ice-Cream Cones 0 需求减少 Decrease in demand 收入增加… An increase in income... D2 D1
相关物品的价格 需求量变动与需求变动 Prices of related Goods Change in Quantity Demande 替代品和互补品 versus Change in Demand Substitutes Complements 影响需求量的变量 这些变量的变动将 当一种商品的价格下跌减少了对另一种商 Quantity Demanded 品的需求,这两种商品被称为替代品 价格Pce 面的事动 When a fall in the price of one good reduces the demand for another good, the two 收入 goods are called substitutes. 相关商品价格 ◆当一种商品的价格下跌增加了对另一种商 品的需求,这两种商品被称为互补品。 When a fall in the price of one good 围荆 Expectations increases the demand for another good, the 购买人数 two goods are called complements. Number of buyers 供给 决定供给的因素 Supply Determinants of Supply 供给量是卖者愿意而且能够出售的数量。 ◆市场价格 Market price Quantity supplied is the amount of a ◆投入品价格 Input prices good that sellers are willing and able to sell ◆技术 Technology ◆预期 Expectations ◆生产商的数量 Number of producers 供给定律 供给表 Law of Supply Supply Schedule 供给定律表述了价格与供给量之间的 正相关性 供给表显示了商品价格与供给量的关系 The law of supply states that there is The supply schedule is a table that shows a direct(positive) relationship the relationship between the price of the good and the quantity supplied. between price and quantity supplied
5 25 相关物品的价格 Prices of Related Goods 替代品和互补品 Substitutes & Complements 当一种商品的价格下跌减少了对另一种商 品的需求，这两种商品被称为替代品。 When a fall in the price of one good reduces the demand for another good, the two goods are called substitutes. 当一种商品的价格下跌增加了对另一种商 品的需求，这两种商品被称为互补品。 When a fall in the price of one good increases the demand for another good, the two goods are called complements. 需求量变动与需求变动 Change in Quantity Demanded versus Change in Demand 影响需求量的变量 Variables that Affect Quantity Demanded 这些变量的变动将 A Change in This Variable . . . 价格 Price 代表沿需求曲线的移动 Represents a movement along the demand curve 收入 Income 移动需求曲线 Shifts the demand curve 相关商品价格 Prices of related goods 嗜好 Tastes 预期 Expectations 移动需求曲线 购买者人数 Number of buyers 移动需求曲线 移动需求曲线 移动需求曲线 27 供给 Supply 供给量是卖者愿意而且能够出售的数量。 Quantity supplied is the amount of a good that sellers are willing and able to sell. 28 决定供给的因素 Determinants of Supply 市场价格 Market price 投入品价格 Input prices 技术 Technology 预期 Expectations 生产商的数量 Number of producers 29 供给定律 Law of Supply 供给定律表述了价格与供给量之间的 正相关性。 The law of supply states that there is a direct (positive) relationship between price and quantity supplied. 30 供给表 Supply Schedule 供给表显示了商品价格与供给量的关系。 The supply schedule is a table that shows the relationship between the price of the good and the quantity supplied