Government microeconomic intervention (A Level)
A-Level Economics Topic 8 8:20 English narration · English + 中文 subtitles burned in
Chapters
Transcript
Three ordinary pictures.
三张普通的照片。
Cigarettes, sold cheaply to anyone who wants them.
香烟，谁想买都买得到，而且很便宜。
A hillside of tin roofs, looking down on a rich city district.
一片铁皮屋顶的山坡， 俯瞰着富裕的城区。
A factory floor, where workers take whatever wage is offered.
一间工厂车间，工人拿着别人给的工资。
In each one the market has done its job. In each one something has still gone wrong.
每一张里，市场都在正常运转；每一张里，仍然有些地方出了错。
This is topic eight, and it has three jobs.
这是第八个专题，它有三项任务。
First, correct market failure — and know when the cure does more harm than the disease.
第一，纠正市场失灵——并且知道什么时候 「药」比「病」更糟。
Second, share income more fairly.
第二，更公平地分配收入。
Third, understand the labour market, where the price is your wage.
第三，理解劳动力市场， 在那里，价格就是你的工资。
A quick reminder from the first year.
先快速回顾第一年学过的内容。
When a factory pollutes, the cost it pays is less than the cost society pays.
当一家工厂排污时，它付出的成本小于社会承担的成本。
The market settles where private cost meets demand, so too much is produced.
市场停在私人成本与需求相交的地方，于是产量过多。
The true social cost is higher, and the best point for society sits further left.
真正的社会成本更高， 社会的最优点更靠左。
That gap is a welfare loss.
这个差距就是福利损失。
Here is the toolkit.
这就是政策工具箱。
An indirect tax raises the price of a harmful good.
间接税提高有害物品的价格。
A subsidy lowers the price of a good that brings extra benefit.
补贴降低带来额外好处的物品的价格。
These are the tools for correcting market failure.
价格管制规定法定的最高价或最低价。
A price control sets a legal maximum or minimum. Tradable permits cap total pollution and let firms trade the right to pollute.
可交易许可证给污染总量设上限，并让企业买卖排污权。
Regulation uses rules and bans; state provision means the government supplies it directly.
管制依靠规则和禁令； 政府提供是指由政府直接供给这种物品。
An industry can also be taken into public ownership — nationalisation — or sold back, which is privatisation.
行业还可以被国有化，或者再次私有化。
Watch one tool at work.
来看其中一个工具如何运作。
A maximum price is set below the market price — a cap on rent, or on fuel.
最高限价被定在市场价格之下——比如租金上限或燃油上限。
At that lower price buyers want more, and sellers offer less.
在这个更低的价格上，买者想要的更多，卖者愿意提供的更少。
The price can no longer clear the market, so a shortage opens.
价格不再能出清市场，于是出现短缺。
Some gain cheap rent. Others queue, or pay far more on a black market.
有些人得到便宜的租金， 另一些人只能排队，或者在黑市上付出高得多的价钱。
Market failure is not only pollution.
市场失灵不只有污染。
A firm with monopoly power raises its price and holds output down, and the market alone will not stop it.
拥有垄断势力的企业会抬高价格、压低产量， 而市场本身阻止不了它。
Competition policy is the law that does.
竞争政策就是做这件事的法律。
It can block a merger that would create too much power. It can ban price fixing — rivals secretly agreeing prices. It can fine a dominant firm that abuses its position.
它可以阻止一桩会造成 过大势力的合并；可以禁止价格串通——也就是对手私下商定价格； 可以对滥用地位的支配性企业处以罚款。
Where competition is impossible, a regulator caps the price.
在竞争根本不可能的地方， 则由监管机构来限定价格。
But every cure can fail.
但每一种「药」都可能失败。
Government failure is when the action leaves resources worse used than before.
政府失灵是指：这项行动让资源被使用得比以前更糟。
Four reasons.
有四个原因。
Poor information: nobody knows the true external cost, so the tax is set too high or too low.
信息不足：没有人知道真实的外部成本，于是税定得过高或过低。
Administration: policing a policy costs real money.
行政成本：监督一项政策要花真金白银。
Time lags: by the time it arrives, the problem has changed.
时间滞后：等政策落地， 问题已经变了。
And unintended effects — like the black market we just saw.
还有意料之外的后果——比如我们刚看到的黑市。
Now the second job: fairness.
现在进入第二项任务：公平。
Two words that sound alike and are not.
有两个听起来相像、其实不同的词。
Equality means everyone gets the same share.
平等是指每个人得到相同的份额。
Equity means everyone gets a fair share — and a fair share is not always the same.
公平是指每个人得到应得的份额—— 而应得的份额不一定相同。
Keep one more pair apart.
还有一对也要分清。
Income is a flow received over time: wages, rent, interest.
收入是一段时间里获得的流量： 工资、地租、利息。
Wealth is a stock of assets owned: a house, shares, savings.
财富是拥有的资产存量：房子、股票、储蓄。
Now measuring inequality.
一个国家有多不平等？
How unequal is a country? The Lorenz curve answers it. Line everyone up from poorest to richest, and plot the income received against the share of the population counted.
把所有人从最穷排到最富，然后把他们已经得到的收入， 对着已经数过的人口份额画出来。
Equal earnings would give the straight diagonal — the line of equality.
如果人人挣得一样，就会得到那条直的对角线—— 平等线。
Real countries sag below it.
真实的国家都垂在它下面。
The Gini coefficient is the sagging area A divided by the whole triangle, A plus B.
基尼系数就是下垂的面积 A， 除以整个三角形，也就是 A 加 B。
Zero is perfect equality; one means one person has everything.
零表示完全平等，一表示一个人拥有一切。
Try one.
来试一道。
Country X has a Gini of zero point two five, country Y zero point four eight.
X 国的基尼系数是零点二五，Y 国是零点四八。
What does that tell you about their curves? Pause here.
这告诉你，它们的曲线是什么样子？
A higher number always means more unequal, so Y is clearly more unequal.
先暂停一下。 数字越大，就一定越不平等，所以 Y 国明显更不平等。
On the graph, X hugs the line of equality, while Y's Lorenz curve sags further below it, so the area between them is bigger. One warning: the Gini measures relative inequality only.
在图上，X 国紧贴着平等线；Y 国垂得低得多，两者之间的面积也就更大。
It says nothing about absolute living standards, so a poor country and a rich one can share the same Gini.
有一点要注意：基尼系数只衡量相对份额，而不是谁到底有多富。
What can a government do about that inequality?
政府能做些什么呢？
Three policies to redistribute — that is equity and redistribution.
有三种工具。
A progressive tax takes a higher rate from higher incomes, so the rich pay more than in proportion.
累进税对更高的收入按更高的税率征收， 于是富人缴的比例更高。
Benefits, also called transfer payments, hand money to the poor, the old and the unemployed.
福利金，也叫转移支付，把钱发给穷人、老人和失业者。
And free state services — schooling and health care — lift the living standards of people who could never buy them.
还有免费的公共服务——教育和医疗——提高了那些本来买不起的人的生活水平。
Now the evaluation, where the marks are.
现在到了评价部分，分数就在这里。
High tax rates can weaken the incentive to work, to save and to take risks.
过高的税率会削弱工作、储蓄和承担风险的动力。
Wealth is much harder to reach than income, because assets can be hidden or moved abroad.
财富比收入难触及得多，因为资产可以被藏起来，或者转移到国外。
And if benefits are withdrawn too fast, working more can leave a family barely better off.
而如果福利被收回得太快，多干活反而可能让一个家庭几乎没有变好。
Fairness is always bought with something.
公平永远是用别的东西换来的。
The third job: the labour market.
第三项任务：劳动力市场。
A wage is just a price — the price of labour.
工资只是一种价格——劳动的价格。
The demand for labour is a derived demand: the firm wants the goods those workers make, not the workers.
对劳动的需求是一种派生需求：企业要的是这些工人生产的产品，而不是工人本身。
So for each extra worker it asks: how much extra revenue does that worker bring in?
所以，对每多雇一个人，它只问：这个人能多带来多少收入？
That is the marginal revenue product, and it falls as more are added.
这就是边际收益产品，而且人越多，它越小。
If the wage is sixty, hire while the extra revenue is at least the wage.
如果工资是六十， 那么只要多带来的收入不低于工资，就继续雇。
Four workers are worth hiring; the fifth brings in less.
这里雇四个人是划算的， 第五个人带来的收入更少。
Put that on a diagram and the labour market behaves like any other.
把这件事画成图，劳动力市场就和其他市场一样。
Demand slopes down — at a lower wage firms hire more — and that demand curve is the marginal revenue product.
需求向下倾斜——工资越低， 企业雇得越多——而这条需求曲线就是边际收益产品。
Supply slopes up: a higher wage draws more people in, and it also depends on the training needed and the working conditions.
供给向上倾斜： 工资越高，越多人愿意进来；它还取决于所需的培训和工作条件。
Where the two cross, the wage and the number of jobs are settled together.
两条线相交的地方，工资和就业量就同时被决定了。
Real labour markets are rarely that tidy.
真实的劳动力市场很少这么整齐。
A monopsony is a single dominant buyer of labour — the only large employer in a town.
买方垄断是指劳动的唯一主导买家—— 比如一个镇上唯一的大雇主。
Workers cannot go elsewhere, so it pays below the competitive wage.
工人去不了别处，于是它支付低于竞争水平的工资。
A trade union answers from the other side: workers bargain together and push the wage up, though that may cost jobs.
工会则从另一边回应：工人联合起来议价，把工资推高，尽管这可能损失岗位。
Wages differ anyway — that gap is a wage differential, and it is mostly marginal revenue product, training and danger.
不同工作的工资本来就有差别，主要来自技能、培训和危险程度。
But part of the gap is discrimination.
但这个差距中有一部分来自歧视。
Now the policy the exam loves.
现在来看考试最爱的这项政策。
A national minimum wage is a legal lowest wage — a price floor in the labour market.
全国最低工资是法定的最低工资—— 也就是劳动力市场上的价格下限。
Draw it above the equilibrium.
把它画在均衡之上。
Along the demand curve, firms now want fewer workers. Along the supply curve, more people want the job.
沿着需求曲线，企业现在想雇的人更少；沿着供给曲线，想做这份工作的人更多。
The arrow between them has a name: unemployment.
两者之间那支箭有一个名字：失业。
And notice the condition: below the market wage it would change nothing.
还要注意一个条件： 低于市场工资，就什么也不会改变。
Now write the answer.
现在来写答案。
A minimum wage is set above the equilibrium in a competitive labour market.
在一个竞争性劳动力市场上，最低工资被定在均衡之上，分析其影响。
Analyse the effect. Pause and plan it.
先暂停，把答案想好。
Step one: firms demand less labour.
第一步：企业需要的劳动更少。
Step two: more workers offer to supply it.
第二步：更多工人愿意提供劳动。
Step three: the gap is excess supply — unemployment.
第三步：两者之间的差额就是过度供给——失业。
Step four, the evaluation: those who keep their jobs gain, those who lose them do not.
第四步，也就是评价：保住工作的人得益，失去工作的人变差。 所以要看情况。
So it depends. If labour demand is inelastic, few jobs go.
如果劳动需求缺乏弹性，失去的岗位就很少。
And in a monopsony the result flips — the wage and employment can both rise.
而在买方垄断中，结论会反过来—— 工资和就业可以同时上升。
Three habits before you go.
结束之前，三个习惯。
First, never stop at naming a policy: say how it works, then say what can go wrong with it.
第一，不要只说出政策的名字：先说它怎么起作用， 再说它可能出什么问题。
That second half is government failure — the evaluation marks.
后面这一半就是政府失灵——评价分就在那里。
Second, equity is not equality: equity means fair, equality means the same.
第二，公平不等于平等：公平是指应得，平等是指相同。
Third, the demand for labour is derived — it comes from the demand for what those workers make.
第三，对劳动的需求是派生需求——它来自人们对这些工人所生产东西的需求。