在A Level考试中，AS和A2的占比相同，但是难度却大相径庭。在AS考试中拿一个相对较高的分数（90+/100）非常非常重要！这样的话A2就会轻松很多。复习过程中，对知识点的梳理非常重要，我AS拿高分的秘籍就是一遍又一遍的整理笔记（mind map/纸上勾勾画画/认真梳理 etc.各种整理方法）。
1.Basic Economic Ideas and Resource Allocation
2.Price System and the Microeconomiy
3.Government Microeconomic Intervention
5.Government Macroeconomic Intervention
1.Scarcity, Choice and Opportunity Cost
2.Positive Statements and Normative Statements
3.Factors of Production and their Rewards
4.Resource Allocation in Different Economic Systems and Issues of Transition
5.Production Possibility Curves
money&classification of goods这两个小话题会放在Price system里面，因为money和price更相关，classification of goods和elasticity更相关。
Scarcity, Choice and Opportunity Cost
A situation that arises because people have unlimited wants in the face of limited resources People always have to make choices and prioritize the consumption of commodities.
The opportunity cost of a choice is the value of the next best alternative forgone.
在上面那个例子中，你放弃了巧克力和牛奶两件商品，但是你的opportunity cost是巧克力对你的价值，而并非牛奶或巧克力和牛奶的价值。因为OC指的是放弃了的第二优选择的价值(the value of next best alternative forgone)。机会成本也是经济学里一个非常重要的概念。无论是个人、企业还是政府做选择都会考虑到机会成本，因为资源是有限的。
It is a key assumption made in economics. It means all other things are held constant or are equal.
Positive Statements and Normative Statements
学会分辨 “fact and fiction”很重要。
They are objective statements based on factual evidence. They can be tested and can consequently be rejected or accepted.
客观观点里经常出现“will”“is”这样的单词，比如：The price will fall as the demand decreases.
They are subjective statements based on value judgments. It cannot be tested by factual evidence.
主观观点里经常出现“should”“better””best”这样的单词，比如：Government should put inflation control as top priority.这些Normative Statements可能会影响经济政策，不同的经济学家用同样的数据可能会进行不一样的衡量和假设。因此，Normative和Positive Statements都很重要。
Factors of Production and their Rewards
Economic Resources are the factors of production. These include:
Natural resources such as oil, coal, wheat, water.
It can also be physical space for fixed capital.
人力成本，同时也是the workforce of the economy.
Entrepreneur is someone who take risks, innovates, and uses the FOP. Resources are drawn together into the production process.
Reward:interest from the investment; dividends.
Specialization and division of labor
It occurs when each worker completes a specific task in a production process. Through division of labor, productivity can increase. Firms can then take advantage of increased efficiency and lower average costs of production.
通过分工（专业人做专业事/流水线生产）1. 生产率可以提高 2. 平均成本降低。Specialization可以存在于个人、企业、地区、国家中。
Higher output and potentially higher quality, since production focuses on what people and businesses are best at.
There could be a greater variety of goods and services produced.
3.economies of scale的机会增多，市场规模增大。
There are more opportunities for economies of scale, so the size of the market increases.
There is more competition and this gives an incentive for firms to lower their costs, which helps to keep prices down.
Work becomes repetitive, which could lower the motivation of workers, potentially affecting quality and productivity. Workers could become dissatisfied.
By producing a lot of one type of good through specialization, variety could in fact decrease for consumers.
There could be higher worker turnover for firms, which means employees become dissatisfied with their jobs and leave regularly.
Short run, long run, and very long run
In the short run, at least one factor of production is fixed.
This means there is a limit to the extent it can respond to price changes.
In the long run, all factors of production are variable.
This means firms can increase their capacity by increasing their factors of production.
In the very long run, the firm’s factors of production are variable, as are the inputs
beyond their control.
This means land, labor, capital and entrepreneurship are variable, as are government rules and technology.
Resource Allocation in Different Economic Systems
Free market economy
Government leaves markets to their own devices, so the market force of supply and demand allocate scarce resources.
Three questions to be answered:
1.What to produce ：determined by what consumer prefers.
2.How to produce it? : producers seek profits.
3.For whom to produce it? : whoever has the greatest purchasing power in the economy, and is therefore able to buy the good.
1.Firms are likely to be efficient因为他们需要提供顾客需要的服务和商品。他们需要降低自己的平均成本，更好的利用有限资源。
2.The bureaucracy from government intervention is avoided.
3.Freedom gained from having a free economy leads to more personal freedom.
The free market ignores inequality, and tends to benefit those who hold most of the wealth. There are no social security payments for those on low incomes.
There could be monopolies, which could exploit the market by charging higher prices.
3.demerit good的过度消费和merit good的供给不足。
There could be the over-consumption of demerit goods, which have large negative externalities, such as tobacco. Merit goods, such as education, are under-provided.
Public goods are not provided in a free market, such as national defense.
This is where the government allocates all of the scarce resources in an economy to where they think there is a greater need. It is also referred to as central planning.
It might be easier to coordinate resources in times of crises, such as wars.
The government can compensate for market failure, by reallocating resources. They might ensure everyone can access basic necessities.
Inequality in society could be reduced, and society might maximise welfare rather than profit.
The abuse of monopoly power could be prevented.
They may not necessarily meet consumer preferences.
2.It limits democracy and personal freedom.
Three questions to be answered：
What to produce: determined by what the government prefers.
How to produce it: governments and their employees.
For whom to produce it: who the government prefers.
混合性经济体是现实生活中最常见的；具有上面两种市场的特征。政府会提供public good （比如路灯，道路，警察）and merit good（比如教育，health care system）。
This has features of both planned and free economies and is the most common economic system today. There are different balances between planned and free economies in reality.
Three questions to be answered:
What to produce: determined by both consumer and government preferences.
How to produce it: determined by producers making profits and the government.
For whom to produce it: both who the government prefers and the purchasing power of private individuals.
Production Possibility Curves
Production possibility curves (PPC) depict the maximum productive potential of an economy, using a combination of two goods or services, when resources are fully and efficiently employed.
PPC也可以展示economic growth或者economic decline：
通过economic growth （outward shift of PPC），可以达到E点。因为只有PPC线上和PPC内部的点是可达到的(attainable)。但是只有PPC线上的点是efficiently used，内部的点全部都是inefficient，因为没有合理运用resources。
如果没有经济增长的话，能达到PPC线外的点的唯一途径就是trade—和另外一个经济体合理交易。（通过comparative advantage以及terms of trade）
If the PPC is a straight line, the marginal* opportunity cost is constant. This is because the amount of one good given up to produce the other does not change.
This is not realistic because resources are not fully adjustable to produce both good A and good B.
Define margin:margin的意思是边际，这个概念在以后会有很多用处（比如边际成本，边际效益）有句话说：理性人思考边际（rational people think of margin.）考虑到margin意味着考虑下一步行动。
Economic theory suggests that each extra unit of a good or service consumed gives the consumer less utility. This is the law of diminishing marginal returns.
margin意味着 consume one more unit所多出来的东西，比如marginal utility：the extra utility gain from consuming one more unit of good.
The concave shape of the PPF shows increasing opportunity cost. This is more realistic than the straight line. Producing more of good B decreases the relative output of B and leads to a relatively higher loss of the output of A.
以上就是Top 1 Basic Economic Ideas and Resource Allocation的知识点梳理！希望能为大家的备考带来帮助！
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