2023 AQA IAL Economics (9640) 模擬試題連答案詳解

In monopolistic competition, barriers to entry are low. The presence of short-run supernormal profits attracts new entrants into the industry. As new firms enter with differentiated products, consumers have more choices, which shifts the demand (average revenue) curve for each existing firm's product to the left. Additionally, the availability of more close substitutes makes the individual demand curve more price elastic. Entry continues until only normal profits are made, where the demand curve is tangent to the average total cost curve.

Award 1 mark for the correct option (B).
Reject all other options.

A perfectly contestable market is defined by the absence of entry and exit barriers, which means there are zero sunk costs. Sunk costs are costs that cannot be recovered when a firm leaves an industry (such as highly specialised marketing or machinery). The absence of sunk costs allows for 'hit-and-run' entry, where new firms enter the market when supernormal profits are available and exit costlessly if profits fall.

Award 1 mark for the correct option (B).
Reject all other options.

Under \( RPI - X \) price regulation, the maximum percentage price increase a firm can implement is equal to the rate of inflation minus the efficiency factor \( X \). Here, maximum price change = \( 3\% - 4\% = -1\% \). This means that nominal prices must decrease by at least 1% per year.

Award 1 mark for the correct option (B).
Reject all other options.

Regulatory capture occurs when a regulatory agency, created to act in the public interest, instead advances the commercial or political concerns of special interest groups that dominate the industry it is charged with regulating. This leads to lenient regulatory decisions, such as setting generous price caps or ignoring anti-competitive behaviour, which benefits the firms at the expense of consumers.

Award 1 mark for the correct option (C).
Reject all other options.

When a profession requires highly specialised skills and a long training period, the supply of labour cannot respond quickly to changes in the wage rate. In the short run, even a large increase in wages will not immediately attract new qualified workers because of the time lag required to acquire the training. Thus, the supply of labour is highly price (wage) inelastic in the short run.

Award 1 mark for the correct option (A).
Reject all other options.

The supply of labour is determined by both pecuniary factors (wages, bonuses) and non-pecuniary factors (working conditions, job security, flexible hours, holidays). A non-pecuniary benefit refers to a non-monetary benefit. An improvement in working conditions and flexible hours makes the job more attractive, shifting the labour supply curve to the right at any given wage rate. Options A and B are pecuniary benefits, and Option D would decrease the attractiveness of the job, shifting the supply curve to the left.

Award 1 mark for the correct option (C).
Reject all other options.

A progressive income tax system taxes high-income earners at a higher percentage rate than low-income earners. This redistributes income, reducing post-tax income inequality. A decrease in inequality shifts the Lorenz curve closer to the 45-degree line of perfect equality and reduces the Gini coefficient (which moves closer to 0, representing perfect equality).

Award 1 mark for the correct option (B).
Reject all other options.

Means-tested benefits are only paid to individuals whose income or wealth falls below a certain threshold. As these individuals earn more income from working, their benefits are gradually withdrawn. When combined with income taxes and national insurance contributions, this withdrawal of benefits creates a very high effective marginal tax rate, reducing the incentive to work or work longer hours. This situation is known as the 'poverty trap' or 'unemployment trap'.

Award 1 mark for the correct option (B).
Reject all other options.

In a highly contestable market, the threat of 'hit-and-run' entry by new competitors is high due to low barriers to entry and exit. To deter these potential entrants, incumbent firms will lower their prices and increase output, moving closer to the point where price equals average cost (earning normal profit).

1 mark for the correct answer: b. No marks for incorrect options.

The elasticity of supply of labour measures how responsive the quantity of labour supplied is to a change in the wage rate. When there is a high degree of occupational mobility, workers can easily transfer their skills between jobs. Consequently, a small increase in the wage rate of one occupation will quickly attract a large number of workers, making the labour supply highly wage elastic.

1 mark for the correct answer: b. No marks for incorrect options.

To calculate the price elasticity of supply of labour (\(PES_L\)):

1. Calculate the percentage change in the quantity of labour hours supplied:
\[\%\Delta Q_L = \frac{48,000 - 40,000}{40,000} \times 100 = \frac{8,000}{40,000} \times 100 = 20\%\]

2. Calculate the percentage change in the wage rate:
\[\%\Delta W = \frac{13.50 - 12.00}{12.00} \times 100 = \frac{1.50}{12.00} \times 100 = 12.5\%\]

3. Calculate \(PES_L\):
\[PES_L = \frac{\%\Delta Q_L}{\%\Delta W} = \frac{20}{12.5} = 1.6\]

- **1 mark** for calculating both percentage changes correctly (\(20\%\) and \(12.5\%\)) or for showing the correct formula: \(\frac{\% \text{ change in quantity of labour supplied}}{\% \text{ change in wage}}\).
- **1 mark** for the correct final answer of **1.6** (accept 1.6 or +1.6).

To find the maximum allowed price change, apply the given formula:
\[\text{Price Cap} = RPI - X + K\]

Substitute the values:
\[\text{Price Cap} = 5.4\% - 2.1\% + 1.5\%\]
\[\text{Price Cap} = 3.3\% + 1.5\% = 4.8\%\]

- **1 mark** for showing the correct substitution into the formula: \(5.4 - 2.1 + 1.5\).
- **1 mark** for the correct final answer of **4.8%** (accept 4.8).

To calculate the total supernormal profit:

1. Find the supernormal profit per unit, which is the difference between Price (Average Revenue) and Average Total Cost:
\[\text{Profit per unit} = AR - ATC = £18.50 - £14.50 = £4.00\]

2. Multiply the profit per unit by the total output:
\[\text{Total Supernormal Profit} = \text{Profit per unit} \times \text{Output} = £4.00 \times 2,500 = £10,000\]

- **1 mark** for identifying the correct profit per unit of \(£4.00\) or showing the correct formula: \((AR - ATC) \times Q\).
- **1 mark** for the correct final answer of **£10,000** (accept 10,000).

An excellent diagram will include: 1. Axes: Vertical axis labelled Price, Revenue, Cost (\(P, R, C\)) and horizontal axis labelled Quantity (\(Q\)). 2. Demand curves: A downward-sloping Average Revenue (\(AR\)) curve and a steeper Marginal Revenue (\(MR\)) curve starting from the same vertical intercept, with \(MR\) lying below \(AR\). 3. Cost curves: A U-shaped Marginal Cost (\(MC\)) curve and a U-shaped Average Cost (\(AC\)) curve. 4. Equilibrium: The profit-maximising output \(Q_1\) is identified where \(MC = MR\). 5. Price determination: At \(Q_1\), the price \(P_1\) is determined by projecting vertically up to the \(AR\) curve. 6. Tangency (Normal Profit): In the long run, entry of new firms shifts the demand curve left until the \(AC\) curve is tangent to the \(AR\) curve at precisely \(Q_1\) (so \(Price = AC\) at \(Q_1\)). The minimum point of the \(AC\) curve must be to the right of \(Q_1\).

For the diagram: - 1 mark: Correctly labelled axes (Price/Cost/Revenue and Quantity) plus downward-sloping \(AR\) and \(MR\) curves (where \(MR < AR\)). - 1 mark: Correctly drawn, U-shaped \(MC\) curve, establishing the profit-maximising quantity \(Q_1\) where \(MC = MR\). - 1 mark: Correctly drawn, U-shaped \(AC\) curve that is tangent to the \(AR\) curve at the output level \(Q_1\). - 1 mark: Correctly identifying the long-run equilibrium price \(P_1\) at the point of tangency (where \(P_1 = AC_1\)), showing only normal profits are made. Acceptable alternatives: Minor variations in U-shapes of cost curves, as long as they satisfy standard economic properties (e.g., \(MC\) must pass through the minimum point of \(AC\) to the right of \(Q_1\)). Reject: Diagrams showing short-run supernormal/subnormal profit (where \(AC\) does not touch \(AR\) at \(Q_1\)), or \(AC\) intersecting \(AR\) twice.

A rise in the qualification requirements to enter a profession acts as a significant barrier to entry. Because entering the profession now requires higher levels of education, the time and financial costs of qualifying increase. Fewer potential workers will be willing or able to undertake this additional training, which reduces the number of individuals available at any given wage rate. As a result, the labour supply curve shifts to the left. Additionally, this makes the supply of labour more wage inelastic in the short run, as workers cannot easily or quickly enter the occupation in response to a wage increase due to the time-lag of acquiring qualifications.

1 to 2 marks: Identifies that the supply of labour will decrease or shift to the left, or makes a basic reference to higher qualifications acting as a barrier to entry. 3 to 4 marks: Provides a clear, logical, and fully developed explanation of why the supply curve shifts to the left (explaining the increased cost or time of training, which reduces the pool of qualified applicants) or how it makes the supply curve more wage inelastic.

A rise in the qualification requirements to enter a profession acts as a significant barrier to entry. Because entering the profession now requires higher levels of education, the time and financial costs of qualifying increase. Fewer potential workers will be willing or able to undertake this additional training, which reduces the number of individuals available at any given wage rate. As a result, the labour supply curve shifts to the left. Additionally, this makes the supply of labour more wage inelastic in the short run, as workers cannot easily or quickly enter the occupation in response to a wage increase due to the time-lag of acquiring qualifications.

1 to 2 marks: Identifies that the supply of labour will decrease or shift to the left, or makes a basic reference to higher qualifications acting as a barrier to entry. 3 to 4 marks: Provides a clear, logical, and fully developed explanation of why the supply curve shifts to the left (explaining the increased cost or time of training, which reduces the pool of qualified applicants) or how it makes the supply curve more wage inelastic.

To answer this question, candidates need to analyze the data in Extract A to identify both supporting and conflicting evidence regarding the relationship between NMW increases and youth unemployment.

**Evidence supporting the view:**
* **Overall Trend (2018 to 2022):** The National Minimum Wage increased from $8.00 to $10.00 (a 25% increase), while youth unemployment rose from 12.0% to 13.0% (a rise of 1.0 percentage point).
* **Specific Periods:** Between 2019 and 2021, as the NMW rose from $8.50 to $9.50, youth unemployment rose steadily from 11.5% to 14.0% (an increase of 2.5 percentage points).

**Evidence contradicting/not supporting the view:**
* Between 2018 and 2019, the NMW rose from $8.00 to $8.50, but youth unemployment decreased from 12.0% to 11.5%.
* Between 2021 and 2022, the NMW rose from $9.50 to $10.00, but youth unemployment decreased from 14.0% to 13.0%.

**Conclusion:**
Therefore, the data only partially supports the view because the expected positive relationship does not hold consistently across all annual periods, suggesting other macroeconomic factors may be influencing youth unemployment in Zetland.

**Mark scheme:**

* **2 marks** for identifying and explaining evidence from the data that **supports** the view (including specific data points/calculations).
* **1 mark** for identifying and explaining evidence from the data that **contradicts/does not support** the view (including specific data points/calculations).
* **1 mark** for offering a balanced **overall conclusion** on the extent to which the data supports the view.

*Max 4 marks.*

### Key Points to Analyze:

1. **Impact on the Distribution of Wealth:**
- **Reduction in Inequality:** A progressive wealth tax directly targets the accumulated stock of assets (such as real estate, equities, and savings) of the wealthiest individuals. Because the tax rate rises with the level of wealth, it disproportionately reduces the net assets of the very rich. The tax revenue generated can be used by the government to fund progressive public spending (e.g., education, healthcare, infrastructure, or targeted cash transfers), which helps low-income and asset-poor households build their own human and financial capital, narrowing the wealth and income gap over time. This would be reflected in a shift of the Lorenz Curve closer to the line of perfect equality and a decrease in the Gini coefficient.
- **Limitation:** Wealth valuation can be highly complex (e.g., valuing private business shares, art, or intellectual property), which may lead to tax avoidance, legal loopholes, and undervaluation, limiting the actual redistributive effect.

2. **Impact on Economic Incentives:**
- **Incentive to Invest and Save:** A high marginal wealth tax reduces the net-of-tax return on savings and capital accumulation. This may discourage domestic investment and reduce the pool of capital available for start-ups and business expansion, potentially slowing down long-run economic growth and productivity gains.
- **Capital Flight and Brain Drain:** Highly mobile high-net-worth individuals may choose to relocate their assets or themselves to low-tax jurisdictions (tax havens) to avoid the tax. This capital flight reduces the tax base and can lead to a net loss in tax revenue (aligning with the Laffer Curve theory).
- **Incentive to Work and Entrepreneurship:** Heavy taxation on wealth accumulation may reduce the incentive for entrepreneurs to build highly successful, large-scale businesses, as a significant portion of their ownership stake would be taxed annually. Conversely, some argue that a wealth tax incentivizes asset holders to invest in highly productive, high-yield assets rather than keeping wealth in idle, unproductive assets (like luxury real estate) to cover their tax liabilities.

**Marking Scheme:**

* **Level 3 (9–12 marks):** Detailed, clear, and focused analysis of the impact of a progressive wealth tax on both the distribution of wealth and economic incentives. Strong use of economic theory and terminology (e.g., Gini coefficient, Lorenz curve, capital flight, Laffer curve, incentives). Effective application to the context of the extracts (e.g., Solaria, high wealth concentration, risk of capital flight).
* **Level 2 (5–8 marks):** Developed analysis but may lack depth or balance, focusing more on one aspect (distribution of wealth) than the other (incentives) or vice versa. Some appropriate economic concepts used, but explanations may not be fully developed or lack precision. Some application to the context.
* **Level 1 (1–4 marks):** Descriptive response with little or no systematic economic analysis. Errors or lack of clarity in economic concepts. Minimal or no application to the context.

*Accept/Reject Notes:*
- **Accept:** Diagrammatic analysis, such as a Lorenz Curve diagram showing a shift towards equality, although not strictly required for top marks.
- **Reject:** Simple assertions without economic reasoning (e.g., 'taxing the rich is good because it makes things fair').

### Introduction
- Define **privatisation** (the transfer of state-owned assets to the private sector) and **public ownership** (state ownership and control of industries).
- Define key economic efficiency concepts: **productive efficiency** (minimising average costs, where production occurs at the lowest point of the \(ATC\) curve), **allocative efficiency** (allocating resources to align with consumer preferences, where price equals marginal cost, \(P = MC\)), and **dynamic efficiency** (efficiency over time through investment and innovation).

### Arguments that Privatisation Leads to Greater Efficiency
- **Reduction in X-inefficiency:** Under public ownership, a lack of profit motive and state-backed funding can lead to organisational slack. Privatisation introduces the profit motive and shareholder accountability, incentivising managers to minimise waste and cut unnecessary costs, driving productive efficiency.
- **Dynamic Efficiency and Investment:** Private firms can access capital markets freely to fund major infrastructure projects, whereas public sector firms are constrained by government borrowing limits and fiscal targets. This can lead to superior technology and long-term efficiency gains.
- **Market Discipline and Competition:** If privatisation is accompanied by deregulation (allowing new entrants), competition will force firms to lower prices and improve service quality to retain customers, moving closer to allocative efficiency.
- **Reduced Political Interference:** Privatised firms make decisions based on commercial viability and long-term market signals rather than short-term political considerations (e.g., delaying necessary price rises or infrastructure investments to win votes).

### Arguments that Public Ownership is More Efficient (or Privatisation Fails)
- **Natural Monopoly Market Failure:** Many utilities (like water and rail networks) have high sunk costs and significant economies of scale, making them natural monopolies. Competing networks are allocatively inefficient. A privatised natural monopoly has market power to restrict output and charge high prices (\(P > MC\)), exploiting consumers and creating deadweight loss.
- **Neglect of Positive Externalities:** Public utilities often generate positive externalities (e.g., clean water public health benefits, rail transport reducing road congestion). Profit-maximising private firms ignore these external benefits, leading to underprovision or underinvestment relative to the socially optimum level.
- **Inadequate Regulation:** To prevent monopoly abuse, governments must establish regulatory bodies (e.g., Ofwat, Ofreg). However, regulation is costly, subject to **regulatory capture** (where the regulator protects the interests of the firm rather than consumers), and can suffer from asymmetric information, failing to secure allocative efficiency.

### Evaluation and Conclusion
- Privatisation does not *always* lead to greater economic efficiency; the outcome is highly conditional.
- **The Role of Competition:** Privatising a monopoly without introducing competition simply converts a public monopoly into a private monopoly, which rarely improves allocative efficiency without heavy state control.
- **The Quality of Regulation:** The success of privatisation depends heavily on the regulator's ability to set challenging efficiency targets (such as \(RPI - X\) price caps) that mimic competitive pressures.
- **Industry Specifics:** Capital-intensive networks with massive externalities (e.g., rail infrastructure) may be structurally better suited to public ownership, whereas competitive retail utility markets (e.g., telecoms) thrive under private ownership.

### 25-Mark Essay Marking Descriptor

**Level 5 (21–25 marks):**
- Demonstrates excellent, relevant economic understanding of privatisation, public ownership, and various forms of efficiency (allocative, productive, dynamic, and X-inefficiency).
- Applies economic concepts and theories highly effectively to the context of public utilities (e.g., natural monopoly, externalities, regulatory capture).
- Structured, logical, and coherent analysis of both sides of the debate.
- Provides a well-reasoned, critical evaluation throughout, culminating in a balanced and justified conclusion.

**Level 4 (16–20 marks):**
- Strong understanding of the economic impacts of privatisation and public ownership.
- Good application of economic theories, using appropriate terminology.
- Balanced analysis of the advantages and disadvantages of privatisation vs. public ownership, though some areas may lack depth.
- Includes an evaluative conclusion, though it may not be fully developed or integrated throughout the essay.

**Level 3 (11–15 marks):**
- Shows reasonable economic understanding of privatisation and efficiency.
- Application to utilities is present but may be generalised.
- Analysis is structured but tends to be one-sided or lacks depth in economic theory (e.g., lacks clear distinction between different types of efficiency).
- Evaluative comments are present but superficial or assertion-based.

**Level 2 (6–10 marks):**
- Limited understanding of privatisation and public ownership.
- Weak application to the utility sector; concepts are defined but not well applied.
- Analysis is descriptive rather than analytical.
- Little or no evaluation present.

**Level 1 (1–5 marks):**
- Very basic awareness of the topic. Demonstrates significant errors or omissions in economic theory.
- No meaningful analysis or evaluation.

### Introduction
- **Definitions:**
- **Income** is a flow of earnings (e.g., wages, interest, dividends) over a period of time.
- **Wealth** is a stock of accumulated assets (e.g., property, pension funds, shares) at a point in time.
- **Relative poverty** refers to households with income significantly below the average (e.g., less than 60% of median income).
- **Economic inequality** refers to the unequal distribution of income and wealth across society, often measured by the Lorenz curve and the Gini coefficient.
- **Overview of the Debate:** While wealth inequality is typically far more extreme than income inequality, economists debate whether targeting the stock of wealth directly is superior to targeting income flows and redistributing them via welfare benefits.

### Arguments for a Wealth Tax being More Effective
- **Targeting the Root of Inequality:** Wealth inequality is cumulative and self-reinforcing. A wealth tax directly reduces the concentration of capital at the top, lowering the Gini coefficient for wealth.
- **Revenue Generation for Poverty Alleviation:** If successfully implemented, even a low-rate annual wealth tax (e.g., 1-2% on fortunes over a certain threshold) can raise substantial government revenue. These funds can be redistributed to alleviate relative and absolute poverty through investment in merit goods like education, healthcare, and infrastructure.
- **Addressing Unearned Income:** A wealth tax targets wealth inherited or accumulated through asset price inflation, which does not reflect current productive economic activity, thereby improving vertical equity.

### Arguments for Progressive Income Taxes and Welfare Benefits being More Effective
- **Administrative Feasibility and Cost:** Income is relatively easy to measure, track, and tax at source (e.g., PAYE systems). In contrast, wealth is difficult to value annually (e.g., private business equity, fine art, real estate), leading to high administration and compliance costs.
- **Avoidance and Capital Flight:** Wealth is highly mobile. High net-worth individuals can easily relocate assets offshore or move their tax residency, eroding the tax base and potentially harming domestic investment.
- **The Liquidity Problem:** Some individuals may be 'asset-rich but cash-poor' (e.g., pensioners living in high-value houses). A wealth tax would force them to sell assets to pay the tax, creating perceived unfairness.
- **Direct Impact of Welfare Benefits:** Welfare transfers (e.g., universal credit, pensions, disability allowances) have an immediate and direct impact on the disposable income of the poorest households. Because the poor have a high marginal propensity to consume (MPC), these transfers directly alleviate material deprivation and boost aggregate demand.

### Evaluation and Synthesis
- **Complementary Roles:** Rather than being mutually exclusive, the two policy suites are most effective when used together. A progressive income tax system captures ongoing economic rewards, while targeted wealth taxes (such as inheritance/gift taxes, which are easier to administer than annual wealth taxes) prevent the permanent entrenchment of dynastic wealth.
- **The Equity-Efficiency Trade-off:** Extremely high progressive taxes (on wealth or income) can create disincentives to work, save, and take entrepreneurial risks, potentially shrinking the overall size of the economic pie and hurting long-run growth.
- **Conclusion:** A wealth tax, while theoretically appealing to target extreme asset concentration, is practically flawed. Progressive income taxes combined with a well-targeted, means-tested welfare state remain the most reliable and stable mechanism for reducing income inequality and alleviating poverty in a modern economy.

### Mark Scheme (25 Marks Max)

| Level | Marks | Descriptor |
|---|---|---|
| **Level 5** | **21–25** | • Excellent focus on the question throughout.
• Strong, precise economic terminology used correctly.
• Well-structured, logical chains of economic analysis showing both sides of the debate.
• Balanced and highly effective evaluation that reaches a reasoned, supported conclusion. |
| **Level 4** | **16–20** | • Good focus on the question.
• Clear economic analysis with good chains of reasoning, though some minor omissions may occur.
• Good evaluation of wealth taxes vs income taxes/welfare benefits, leading to a logical conclusion. |
| **Level 3** | **11–15** | • Reasonable focus on the question.
• Some structured analysis of poverty-reduction policies, but may lack depth or contains minor logical errors.
• Evidence of evaluation, but it may be brief or rely on unsubstantiated assertions. |
| **Level 2** | **6–10** | • Limited focus on the question, often descriptive rather than analytical.
• Basic understanding of tax or welfare, but lacks rigorous economic reasoning.
• Weak or absent evaluation. |
| **Level 1** | **1–5** | • Very limited response showing major misconceptions or lacking relevant economic framework. |

**Key Points to Look For:**
- **Analysis of Wealth Taxes:** Mechanism of taxing the stock of assets; potential to reduce wealth inequality; funding public services.
- **Analysis of Income Taxes & Welfare:** Flow vs stock distinction; direct impact of progressive income tax; effectiveness of welfare benefits (cash transfers, housing subsidies) on the lowest quintiles.
- **Evaluation Points:** Valuability and liquidity issues of wealth; tax evasion and capital flight; incentive structures (Laffer curve effects); the necessity of a mixed approach.