WJEC A Level Economics
WJEC A Level Economics Market Structures Exam Questions
Free WJEC A Level Economics revision for Market Structures: what you need to know, common mistakes and exam-style questions with answers. Covers business objectives, contestability and barriers to entry, perfect competition, monopolistic competition, monopoly, oligopoly and game theory, competition policy and privatisation.
Practise Market Structures with past papers
Once you have learnt this topic, find the Market Structures questions in real WJEC A Level Economics past papers and mark them with the mark scheme. Doing lots of real questions is the quickest way to learn how examiners ask about each idea.
About WJEC A Level Economics Market Structures
Market structures is the major A2 microeconomics topic in WJEC Economics. It begins with the background to market structures, including barriers to entry and contestability, and with business objectives such as profit maximisation, revenue and sales maximisation and satisficing. You then model perfect competition, monopolistic competition, monopoly and oligopoly, using concentration ratios, limit pricing, collusion, price leadership, price wars and game theory with a Nash equilibrium. The topic finishes with competition policy and privatisation, asking how governments deal with market power. It is examined in A2 Units 3 and 4, and the Unit 4 microeconomics essays often require full diagram analysis and evaluation of efficiency.
What you need to know
- Barriers and contestability Barriers to entry can be structural (economies of scale, high sunk costs, legal protection) or strategic (limit pricing, heavy advertising). In a perfectly contestable market entry and exit are free, so even a few firms behave competitively.
- Business objectives Profit maximisation at MC = MR, revenue maximisation at MR = 0, sales maximisation where AR = AC, and satisficing, where managers aim for enough profit to keep shareholders happy while pursuing other goals.
- Perfect competition Many small firms sell identical products with perfect information and no barriers to entry, so each is a price taker. Short run supernormal profits attract entry until only normal profit remains; the long run outcome is productively and allocatively efficient.
- Monopolistic competition Many firms sell slightly differentiated products and face downward sloping demand. With free entry, long run profits are normal, with AR tangent to AC and excess capacity.
- Monopoly A monopolist faces the industry demand curve, maximises profit at MC = MR and can earn long run supernormal profit behind high barriers. It may be allocatively and productively inefficient, but could achieve economies of scale and dynamic efficiency. Price discrimination can raise profit.
- Oligopoly and game theory A few large interdependent firms, measured by concentration ratios. Firms may collude formally or tacitly, follow a price leader or fight price wars. A payoff matrix shows how each firm's best strategy depends on the rival's choice; the Nash equilibrium explains why firms may fail to cooperate.
- Competition policy and privatisation Competition authorities investigate mergers, cartels and abuse of dominant positions, and regulators may impose price controls. Privatisation sells state owned enterprises to the private sector to raise efficiency, but may need regulation to prevent abuse of market power.
Common mistakes in Market Structures
- Showing long run supernormal profit in perfect competition. Free entry means profits return to normal in the long run.
- Reading the monopoly price off the MC curve. Find output at MC = MR, then go up to the AR curve for the price.
- Describing oligopoly without interdependence. The key feature is that each firm's decisions depend on how rivals are expected to react.
- Treating contestability as the same as many firms. A market with one firm can be contestable if barriers to entry and exit are low.
- Concluding that privatisation always improves efficiency. It depends on competition, regulation and the incentives of the new owners.
Try three Market Structures exam-style questions
1. Two firms, A and B, can each charge a high or low price. If both charge high, each earns £10m. If both charge low, each earns £6m. If one charges low and the other high, the low price firm earns £12m and the high price firm £3m. Identify the Nash equilibrium and explain why. (4 marks)
Show the mark scheme answer
If B charges high, A earns more by charging low (12 vs 10); if B charges low, A earns more by charging low (6 vs 3); so low price is A's dominant strategy, and the same applies to B; the Nash equilibrium is both charging low, earning £6m each, even though both would earn more by colluding at high prices.
2. Explain what is meant by limit pricing. (2 marks)
Show the mark scheme answer
An incumbent firm sets its price low enough (close to or below potential entrants' average cost) to make entry unprofitable; so it deters new firms from entering the market.
3. Evaluate the view that monopoly always works against the interests of consumers. (15 marks)
Show the mark scheme answer
A strong answer would use a monopoly diagram to show higher price, lower output, allocative and productive inefficiency and deadweight loss; then evaluate economies of scale (natural monopoly), dynamic efficiency from supernormal profit, contestability limiting price rises, and regulation by competition authorities; reach a judgement on when monopoly is harmful.
Market Structures FAQs
What does WJEC A Level Economics Market Structures cover?
It covers barriers to entry and contestability, business objectives, perfect competition, monopolistic competition, monopoly, oligopoly with game theory and concentration ratios, competition policy and privatisation.
Which unit is Market Structures examined in?
It is A2 content, so it is examined in A2 Unit 3 (Exploring Economic Behaviour) and A2 Unit 4 (Evaluating Economic Models and Policies).
How do I approach a payoff matrix question?
Take each firm in turn. For each possible choice by the rival, find the firm's best response. If a strategy is best whatever the rival does, it is dominant. The Nash equilibrium is where both firms are making their best response to each other.
