第一章：基本经济概念与市场机制 (Basic Economic Concepts and Market Mechanisms)
1. 稀缺性与机会成本 (Scarcity and Opportunity Cost)
- 定义：资源是有限的，而人类欲望是无限的，这种矛盾就是稀缺性。由于稀缺性，做出一种选择就意味着必须放弃其他最佳选择，所放弃的最佳选择的价值就是该项决策的机会成本。
- Definition: Resources are finite, but human wants are unlimited. This fundamental problem is scarcity. Because of scarcity, making one choice necessitates forgoing the next best alternative. The value of this forgone alternative is the opportunity cost of that decision.
2. 生产要素 (Factors of Production)
- 定义：用于生产商品和服务的资源，通常分为四类：土地（自然资源）、劳动（人力投入）、资本（人造的生产工具，如机器）和企业才能（组织其他要素并承担风险的能力）。
- Definition: Resources used in the production of goods and services. They are typically categorised into four groups: Land (natural resources), Labour (human effort), Capital (man-made aids to production, e.g., machinery) and Enterprise (the ability to organise the other factors and take risks).
3. 生产可能性边界 (Production Possibility Frontier, PPF)
- 定义：一个图表模型，显示在给定资源和技术水平下，一个经济体所能生产的两种商品的最大可能组合。它说明了稀缺性、选择和机会成本。曲线上的点表示资源充分利用，曲线内的点表示资源未充分利用或效率低下，曲线外的点在当前条件下无法达到。
- Definition: A diagrammatic model that shows the maximum possible combinations of two goods an economy can produce given its resources and state of technology. It illustrates scarcity, choice, and opportunity cost. Points on the curve represent full employment of resources, points inside represent underutilisation or inefficiency, and points outside are unattainable with current resources.
4. 分工/专业化 (Division of Labour / Specialisation)
- 定义：将生产过程分解为一系列特定任务，并由不同的工人或地区分别完成。这可以提高熟练度和生产效率。
- Definition: Breaking down the production process into a series of specific tasks, each performed by different workers or regions. This can increase skill and productivity.
5. 需求 (Demand)
- 定义：在特定时间周期内，消费者在不同价格水平上愿意并且能够购买的商品或服务的数量。
- Definition: The quantity of a good or service that consumers are willing and able to purchase at various price levels during a given period of time.
6. 供给 (Supply)
- 定义：在特定时间周期内，生产者在不同价格水平上愿意并且能够提供的商品或服务的数量。
- Definition: The quantity of a good or service that producers are willing and able to offer for sale at various price levels during a given period of time.
7. 市场均衡 (Market Equilibrium)
- 定义：指市场需求量与市场供给量相等时的状态，对应的价格称为均衡价格，数量称为均衡数量。此时市场没有过剩或短缺。
- Definition: The state where market demand equals market supply. The corresponding price is the equilibrium price, and the quantity is the equilibrium quantity. There is no excess supply or demand.
8. 消费者剩余 (Consumer Surplus)
- 定义：消费者对某商品愿意支付的最高价格与实际支付的市场价格之间的差额总和。在需求曲线下方、市场价格水平线上方的区域。
- Definition: The difference between what consumers are willing to pay for a good and what they actually pay (the market price). It is the total area below the demand curve and above the market price line.
9. 生产者剩余 (Producer Surplus)
- 定义：生产者出售某商品实际收到的市场价格与他们愿意接受的最低供给价格之间的差额总和。在供给曲线上方、市场价格水平线下方的区域。
- Definition: The difference between what producers receive for a good (the market price) and the minimum price they would be willing to accept to supply it. It is the total area above the supply curve and below the market price line.
第二章：弹性 (Elasticity)
1. 价格需求弹性 (Price Elasticity of Demand, PED)
- 定义：衡量商品需求量对其价格变动的反应程度。计算公式为：需求量变动百分比 / 价格变动百分比。其值通常为负（遵循需求定律），但分析时通常取绝对值。|PED| > 1 为富有弹性，|PED| < 1 为缺乏弹性。
- Definition: Measures the responsiveness of the quantity demanded of a good to a change in its price. Formula: % change in quantity demanded / % change in price. The value is usually negative (following the law of demand) but is often interpreted in absolute terms. |PED| > 1 is elastic demand, |PED| < 1 is inelastic demand.
2. 价格供给弹性 (Price Elasticity of Supply, PES)
- 定义：衡量商品供给量对其价格变动的反应程度。计算公式为：供给量变动百分比 / 价格变动百分比。PES > 1 为富有弹性，PES < 1 为缺乏弹性。
- Definition: Measures the responsiveness of the quantity supplied of a good to a change in its price. Formula: % change in quantity supplied / % change in price. PES > 1 is elastic supply, PES < 1 is inelastic supply.
3. 收入需求弹性 (Income Elasticity of Demand, YED)
- 定义：衡量商品需求量对消费者收入变动的反应程度。计算公式为：需求量变动百分比 / 收入变动百分比。YED > 0 为正常品（其中 YED > 1 为奢侈品，0 < YED < 1 为必需品），YED < 0 为劣等品。
- Definition: Measures the responsiveness of the quantity demanded of a good to a change in consumer income. Formula: % change in quantity demanded / % change in income. YED > 0 indicates a normal good (YED > 1 is a luxury, 0 < YED < 1 is a necessity). YED < 0 indicates an inferior good.
4. 交叉需求弹性 (Cross Elasticity of Demand, XED)
- 定义：衡量一种商品（A）的需求量对另一种商品（B）价格变动的反应程度。计算公式为：商品A需求量变动百分比 / 商品B价格变动百分比。XED > 0 表示替代品（如茶和咖啡），XED < 0 表示互补品（如汽车和汽油），XED ≈ 0 表示不相关商品。
- Definition: Measures the responsiveness of the quantity demanded of one good (A) to a change in the price of another good (B). Formula: % change in quantity demanded of good A / % change in price of good B. XED > 0 indicates substitute goods (e.g., tea and coffee). XED < 0 indicates complementary goods (e.g., cars and petrol). XED ≈ 0 indicates unrelated goods.
第三章：市场失灵与政府干预 (Market Failure and Government Intervention)
1. 市场失灵 (Market Failure)
- 定义：指自由市场未能有效配置资源，导致社会福祉未达到最大化的状态。即，市场在提供商品和服务时，出现了无效率（如垄断）或不公平的结果。
- Definition: Occurs when the free market fails to allocate resources efficiently, resulting in a loss of social welfare. It is when the market provides an inefficient (e.g., monopoly) or inequitable outcome in the provision of goods and services.
2. 外部性 (Externality)
- 定义：指生产或消费活动对第三方产生的、未通过市场价格反映的成本或收益。
- 负外部性/外部成本 (Negative Externality / External Cost)：对第三方造成的不利影响（如污染）。社会成本 > 私人成本。
- 正外部性/外部收益 (Positive Externality / External Benefit)：对第三方产生的有利影响（如疫苗接种）。社会收益 > 私人收益。
- Definition: The cost or benefit of a production or consumption activity that affects a third party and is not reflected in market prices.
- Negative Externality / External Cost: An adverse effect on a third party (e.g., pollution). Social Cost > Private Cost.
- Positive Externality / External Benefit: A beneficial effect on a third party (e.g., vaccination). Social Benefit > Private Benefit.
3. 公共物品 (Public Goods)
- 定义：具有非排他性（无法阻止未付费者使用）和非竞争性（一个人使用不影响他人使用）的商品。典型的例子是国防和街灯。由于“搭便车”问题，私人市场通常不会提供，导致市场失灵。
- Definition: Goods that are non-excludable (impossible to prevent non-payers from consuming) and non-rivalrous (one person's consumption does not reduce availability for others). Classic examples are national defence and street lighting. Due to the ‘free-rider problem’, they are typically under-provided by the private market, leading to market failure.
4. 信息不对称 (Information Asymmetry)
- 定义：指市场交易中，一方比另一方拥有更多或更优质的信息。这可能导致逆向选择（劣质品驱逐优质品）和道德风险，从而降低市场效率。例如，二手车市场或医疗保险。
- Definition: Occurs in a market transaction when one party has more or better information than the other. This can lead to adverse selection (where ‘bad’ products drive out ‘good’ ones) and moral hazard, reducing market efficiency. Examples include the used car market or health insurance.
5. 间接税 (Indirect Tax)
- 定义：对商品和服务的支出征收的税，如增值税（VAT）或消费税。政府常用于纠正负外部性（如对香烟、塑料征税）。它会增加生产成本，使供给曲线向左上方移动，导致市场价格上升，均衡数量减少。
- Definition: A tax levied on expenditure on goods and services, such as Value Added Tax (VAT) or excise duties. Often used by governments to correct negative externalities (e.g., taxes on cigarettes, plastic). It increases production costs, shifting the supply curve leftwards/upwards, leading to a higher market price and a lower equilibrium quantity.
6. 补贴 (Subsidy)
- 定义：政府向生产者（或消费者）提供的支付，以降低其成本或价格。常用于鼓励具有正外部性的商品的生产或消费（如可再生能源、教育）。它会降低生产成本，使供给曲线向右下方移动，导致市场价格下降，均衡数量增加。
- Definition: A payment from the government to producers (or consumers) to lower their costs or prices. Often used to encourage the production or consumption of goods with positive externalities (e.g., renewable energy, education). It reduces production costs, shifting the supply curve rightwards/downwards, leading to a lower market price and a higher equilibrium quantity.
7. 最高价格管制 (Maximum Price / Price Ceiling)
- 定义：政府设定的低于均衡价格的法定最高价。旨在使必需品（如食品、租金）对消费者更负担得起。这会导致需求量超过供给量，产生短缺，并可能引发黑市。
- Definition: A legal maximum price set by the government below the equilibrium price. Aims to make essential goods (e.g., food, rent) more affordable for consumers. This leads to excess demand (shortage) and may create a black market.
8. 最低价格管制 (Minimum Price / Price Floor)
- 定义：政府设定的高于均衡价格的法定最低价。旨在保护生产者的收入（如农产品、最低工资）。这会导致供给量超过需求量，产生过剩，政府通常需要购买过剩产品。
- Definition: A legal minimum price set by the government above the equilibrium price. Aims to protect producers’ income (e.g., agricultural products, minimum wage). This leads to excess supply (surplus), which the government often has to purchase.
9. 污染许可交易 (Pollution Permits / Tradable Permits)
- 定义：一种基于市场的政府干预手段，用于控制污染（负外部性）。政府设定总污染上限，并发行相应数量的许可。企业可以交易这些许可。这为减少污染提供了经济激励，并能以最低总成本实现减排目标。
- Definition: A market-based form of government intervention to control pollution (a negative externality). The government sets a cap on total pollution and issues a corresponding number of permits. Firms can trade these permits. This creates an economic incentive to reduce pollution and can achieve the reduction target at the lowest overall cost.
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