曼昆经济学原理微观部分第6章.

Rent Control in the Short Run...
Rental Price of Apartment
Supply
Supply and demand for apartments are relatively
inelastic
Controlled rent
Shortage
0
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汽油数量
Rent Control in the Short Run and Long Run
u Rent controls are ceilings placed on the rents that landlords may charge their tenants.
u The goal of rent control policy is to help the poor by making housing more affordable.
Supply, Demand, and Government Policies
u In a free, unregulated market system, market forces establish equilibrium prices and exchange quantities.
u While equilibrium conditions may be efficient, it may be true that not everyone is satisfied.
Price of Gasoline 汽油价格
1. Initially, the price ceiling is not binding... 1.原来，价格上 限没有限制性… $4
P1
Supply 供给
Price ceiling 价格上限
0
Q1
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A Price Ceiling That Is Not Binding...
Price of Ice-Cream
Cone
$4
3
Equilibrium price
Demand 需求
Quantity of Gasoline 汽油数量
The Price Ceiling on Gasoline Is Binding...
Price of Gasoline
P2
P1
4. …resulting in a shortage.
S2 2. …but
when supply falls...
u One economist called rent control “the best way to destroy a city, other than bombing.”
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价格上限如何影响市场结果
当政府实行价格上限时，可能 出现wk.baidu.com种价格：
如果价格上限高于均衡 价格，价格 上限没有限制作用。 如果价格上限低于均衡 价格，价格 上限对市场有限制作用。
S1
Price ceiling
3. …the price ceiling becomes binding...
0
Q1
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Demand
Quantity of Gasoline
Demand
Quantity of Apartments
短期的租金控制...
公寓租金 价格
供给与需求都相
供给
对缺乏弹性
短缺
0
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受控制的租金
需求
公寓数量
Rent Control in the Long Run...
u One of the roles of economists is to use their theories to assist in the development of policies.
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Lines at the Gas Pump
In 1973 OPEC raised the price of crude oil in world markets. Because crude oil is the major input used to make gasoline, the higher oil prices
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How Price Ceilings Affect Market Outcomes
n Two outcomes are possible when the government imposes a price ceiling:
u Example: Gasoline shortage of the 1970s
nonprice rationing
u Examples: Long lines, Discrimination by sellers
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0
Supply
Price ceiling
100
Equilibrium quantity
Demand
Quantity of Ice-Cream
Cones
没有限制作用的价格上限...
冰激凌蛋卷 的价格
供给
$4
3
均衡价格
价格上限
需求
0
100
冰激凌蛋卷的数量
均衡数量
A Price Ceiling That Is Binding...
供给、需求与政府政策
u 在一个自由、无管制的市场系统中，市 场力量实现均衡价格和均衡交易量。
u 这种均衡结果也许是有效的，但并不是 每个人对此都感到满意。
u 经济学家的作用之一就是利用他们的理 论帮助制定政策。
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经济学家把它归咎于限制石油公司对 汽油可以收取的价格的政府管制。
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The Price Ceiling on Gasoline Is Not Binding... 汽油的价格上限没有限制性…
汽油的价格上限有限制性...
汽油价格
P2
S2
2. …但当供给
减少时...
S1
价格上限
P1
4. …导致短缺。
3. …价格上限变为 限制性的...
0
Q1
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需求
Rental Price of Apartment
Because the supply and demand for apartments are more elastic...
Controls on Price... 价格控制…
u Are usually enacted when policymakers believe the market price is unfair to buyers or sellers.
当政策制定者认为市场价格对买者或卖者不公 平时，往往实行价格控制。
冰激凌蛋卷 的价格
均衡价格
供给
$3
2
价格上限
短缺
需求
0
75
125 冰激凌蛋卷的数量
供給量
需求量
How Price Ceilings Affect Market Outcomes
n Effects of Price Ceilings n A binding price ceiling creates ... shortages because QD > QS.
u Result in government-created price ceilings and floors.
这就促使政府实行价格上限和价格下限政策。
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加油站前的长队
1973年，石油输出国组织（ OPEC) 提高了世界石油市场的原油价格。由 于原油是用于生产汽油的主要投入，
较高石油价格减少了汽油供给。
谁对加油站前的长队负责？
reduced the supply of gasoline.
What was responsible for the long gas lines?
Economists blame government regulations that limited the price oil companies could charge for gasoline.
Controls on Price... 价格控制…
Price Ceiling 价格上限
u A legally established maximum price at which a good can be sold. 可以出售一种物品的法定最高价格。
Price Floor 价格下限
u A legally established minimum price at which a good can be sold. 可以出售一种物品的法定最低价格。
ä The price ceiling is not binding if set above the equilibrium price.
ä The price ceiling is binding if set below the equilibrium price, leading to a shortage.
Price of Ice-Cream
Cone
Equilibrium price $3 2
0
Supply
Shortage
Price ceiling
Demand
75
125
Quantity Quantity supplied demanded
Quantity of Ice-Cream
Cones
有限制作用的价格上限...
价格上限如何影响市场结果
n 价格上限的作用
n 有限制作用的价格上限造成... 短缺，因为 QD > QS.
u 例子: 70年代的汽油短缺
非市场价格方式配给
u 例子: 排长队, 卖者歧视
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短期中和长期中的租金控制
u 租金控制——房东能向房客收取的 租金上限。
u 这一政策的目的是帮助穷人更能租 得起住房。
u 一位经济学家称租金控制是“除了 轰炸之外毁灭一个城市的最好方法 ”。
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