Edexcel International A Level Economics
Edexcel International A Level Economics Market Structures and Contestability Exam Questions
Free Edexcel International A Level Economics exam questions for Market Structures and Contestability, with a mark scheme for every pack. Covers efficiency, perfect competition, monopolistic competition, oligopoly, game theory, monopoly, monopsony and contestable markets.
Market Structures and Contestability exam questions
1 question pack of real past exam questions, each with its mark scheme. Do not stop after a few: answer as many as you can without notes, then mark every answer with the mark scheme. The more questions you do, the more quickly you will spot how examiners ask about each idea.
About Edexcel International A Level Economics Market Structures and Contestability
Market structures and contestability is the largest topic in Unit 3 of Edexcel International A Level Economics. You compare how firms behave in different structures, from perfect competition to monopoly, and judge each against different types of efficiency. Oligopoly is studied with concentration ratios, collusion and game theory, and contestability theory explains why even a market with one firm may behave competitively. The topic builds on revenue, costs and profits and leads into government intervention. Examiners expect accurate diagrams for each structure and evaluation of whether market power benefits or harms consumers.
What you need to know
- Efficiency Allocative efficiency: P = MC. Productive efficiency: output at the minimum of AC. Dynamic efficiency: improvements over time through investment and innovation. X-inefficiency: costs above the minimum possible due to lack of competitive pressure.
- Perfect competition Many firms, homogeneous products, perfect information, no barriers to entry. Firms are price takers; supernormal profit in the short run is competed away, so long-run equilibrium is at normal profit and allocatively and productively efficient.
- Monopolistic competition Many firms with differentiated products and low barriers to entry. Short-run supernormal profit, long-run normal profit where AR is tangent to AC.
- Oligopoly A few large interdependent firms, high barriers to entry and high concentration ratios. Collusive behaviour (cartels, tacit collusion) and non-collusive behaviour; game theory shows why firms may compete or cooperate; price wars, limit pricing and predatory pricing.
- Monopoly and monopsony A monopoly is a single seller with high barriers to entry; it sets output where MC = MR and earns supernormal profit. Natural monopolies have falling LRAC over the market. A monopsony is a single buyer with power over suppliers.
- Contestability A market is contestable when barriers to entry and exit are low, especially sunk costs. The threat of hit-and-run entry keeps prices close to normal profit levels.
Common mistakes in Market Structures and Contestability
- Forgetting that firms in perfect competition are price takers. The firm faces a horizontal demand curve where P = AR = MR.
- Drawing the monopoly profit rectangle at the wrong height. It is between AR and AC at the profit maximising output where MC = MR.
- Calculating a concentration ratio wrongly. Add the market shares of the largest n firms.
- Assuming oligopolists always collude. Collusion is illegal in many countries and cartels can break down because members cheat.
- Saying contestable markets must have many firms. Contestability depends on entry and exit conditions, not the number of firms.
Try three Market Structures and Contestability exam-style questions
1. The market shares of the five largest firms in a market are 22%, 18%, 15%, 11% and 9%. Calculate the three-firm concentration ratio. (2 marks)
Show the mark scheme answer
22 + 18 + 15; = 55%.
2. Using game theory, explain why firms in an oligopoly may choose not to collude. (4 marks)
Show the mark scheme answer
Payoff matrix shows each firm's profit depending on the other's decision; each firm has an incentive to cut price or cheat to gain market share; the dominant strategy may be to compete; the outcome is a prisoner's dilemma where both are worse off than if they cooperated; collusion is also illegal.
3. Evaluate whether monopoly is always against the interests of consumers. (12 marks)
Show the mark scheme answer
Monopoly sets price above MC, so allocative inefficiency and loss of consumer surplus; may be X-inefficient; evaluation: economies of scale may lower costs and prices; supernormal profits may fund research and development, giving dynamic efficiency; natural monopolies may be most efficient with one firm; market may be contestable; regulation can limit abuse; supported judgement.
Market Structures and Contestability FAQs
What does Edexcel IAL Economics Market structures and contestability cover?
It covers types of efficiency, perfect competition, monopolistic competition, oligopoly and game theory, monopoly, monopsony and contestable markets.
Which unit is Market structures and contestability examined in?
It is part of Unit 3, Business behaviour.
Which diagrams do I need for market structures?
Learn perfect competition in the short and long run, monopolistic competition in the short and long run, monopoly with supernormal profit, natural monopoly and the kinked demand curve for oligopoly.
