Government Intervention in Markets · 政府对市场的干预
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| price ceiling/praɪs ˈsiːlɪŋ/ | 价格上限 | jià gé shàng xiàn |
| binding/ˈbaɪndɪŋ/ | 有约束力 | yǒu yuē shù lì |
| price floor/praɪs flɔː/ | 价格下限 | jià gé xià xiàn |
| deadweight loss/ˈdedweɪt lɒs/ | 无谓损失 | wú wèi sǔn shī |
| per-unit tax/pɜː ˈjuːnɪt tæks/ | 从量税 | cóng liàng shuì |
| tax incidence/tæks ˈɪnsɪdəns/ | 税收归宿 | shuì shōu guī sù |
When the government sets the price
- Sometimes a government decides the market price is too high or too low.
- So it sets a legal limit, or adds a tax, to change the outcome.
- Each rule moves the market away from its efficient equilibrium.
- And each usually creates a loss that goes to nobody.
当政府来定价
- 有时政府认为市场价格太高或太低。
- 于是它设一个法定限额,或加一道税,来改变结果。
- 每一条规则都把市场推离它有效率的均衡。
- 而且每一条通常都造成一份谁也得不到的损失。
A price ceiling causes a shortage
- A price ceiling 价格上限 is a legal maximum price.
- It only bites when set below equilibrium — then it is binding 有约束力.
- At the low legal price, quantity demanded exceeds quantity supplied — a shortage (think rent control).
价格上限造成短缺
- 价格上限(price ceiling)是法定的最高价格。
- 只有设在均衡之下时它才起作用——这时它是有约束力(binding)的。
- 在这个偏低的法定价格下,需求量超过供给量——出现短缺(想想租金管制)。
Set a price control · 设一个价格管制
A price ceiling below equilibrium creates a shortage; a price floor above it creates a surplus. Drag the control and watch the gap and deadweight loss appear. · 低于均衡的价格上限造成短缺;高于均衡的价格下限造成过剩。拖动管制线,看缺口和无谓损失如何出现。
A price ceiling only affects the market (is binding) when it is set: · 价格上限只有在这样设置时才影响市场(即有约束力):
A ceiling below equilibrium holds the price down and creates a shortage. · 低于均衡的上限把价格压住,造成短缺。
Equilibrium is 5 dollars and 100 units. A price ceiling of 3 dollars gives quantity demanded 140 and quantity supplied 70. What is the size of the shortage? · 均衡是 5 美元、100 单位。3 美元的价格上限使需求量为 140、供给量为 70。短缺有多大?
Shortage = quantity demanded − quantity supplied = 140 − 70 = 70. · 短缺 = 需求量 − 供给量 = 140 − 70 = 70。
A price floor causes a surplus
- A price floor 价格下限 is a legal minimum price.
- It only bites when set above equilibrium.
- At the high legal price, quantity supplied exceeds quantity demanded — a surplus (think a minimum wage or farm price supports).
价格下限造成过剩
- 价格下限(price floor)是法定的最低价格。
- 只有设在均衡之上时它才起作用。
- 在这个偏高的法定价格下,供给量超过需求量——出现过剩(想想最低工资或农产品保护价)。
A binding price floor (like a minimum wage) creates a: · 有约束力的价格下限(如最低工资)造成:
A floor above equilibrium keeps the price high, so quantity supplied exceeds quantity demanded. · 高于均衡的下限使价格居高,于是供给量超过需求量。
Match each policy to its effect. · 把每项政策与它的效果配对。
Ceilings cause shortages, floors cause surpluses, and taxes shrink trade with a deadweight loss. · 上限造成短缺,下限造成过剩,税收缩小交易并带来无谓损失。
Taxes and deadweight loss
- A per-unit tax 从量税 shifts supply up: buyers pay more, sellers keep less, and the quantity traded shrinks.
- The lost trades create a deadweight loss 无谓损失 — a fall in total surplus that reaches no one.
- Tax incidence 税收归宿: the more inelastic side pays the larger share, because it cannot escape by changing quantity.
税收与无谓损失
- 从量税(per-unit tax)使供给上移:买家付得更多,卖家留得更少,成交量缩小。
- 消失的交易造成无谓损失(deadweight loss)——一份谁也得不到的总剩余下降。
- 税收归宿(tax incidence):更缺乏弹性的一方承担更大份额,因为它无法靠改变数量来躲避。
A per-unit tax is placed on a good with very inelastic demand. Who bears most of the tax? · 对一种需求非常缺乏弹性的商品征收从量税。谁承担了大部分税负?
The more inelastic side pays the larger share — here, buyers cannot easily escape. · 更缺乏弹性的一方承担更大份额——这里,买家难以躲避。
The loss of total surplus from trades that no longer happen is called ______ loss. · 因不再发生的交易而损失的总剩余,叫做______损失。
A deadweight loss is surplus that a binding control or tax destroys. · 无谓损失是有约束力的管制或税收所摧毁的剩余。
A price ceiling (below equilibrium) causes a shortage; a price floor (above equilibrium) causes a surplus. A per-unit tax shrinks trade and creates a deadweight loss, and its burden (tax incidence) falls mostly on the more inelastic side.
价格上限(低于均衡)造成短缺;价格下限(高于均衡)造成过剩。从量税缩小交易并造成无谓损失,其负担(税收归宿)主要落在更缺乏弹性的一方。