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How do firms behave in the real-world structures between the two extremes, and how do they compete without price?

Monopolistic competition and oligopoly, interdependence and collusion, game theory, non-price competition, and price discrimination.

A focused CCEA A-Level Economics answer on imperfect competition, covering monopolistic competition and its long-run normal profit, oligopoly and concentration, interdependence, collusion and cartels, game theory and the prisoner's dilemma, non-price competition, and the conditions for price discrimination, with worked game-theory reasoning.

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  1. What this dot point is asking
  2. Monopolistic competition
  3. Oligopoly and interdependence
  4. Price discrimination
  5. Try this

What this dot point is asking

CCEA wants you to explain the two main real-world market structures between the extremes - monopolistic competition and oligopoly - covering their assumptions and outcomes, the interdependence of oligopolists, collusion and cartels, game theory and the prisoner's dilemma, non-price competition, and the conditions for and effects of price discrimination.

Monopolistic competition

In the short run a firm can earn supernormal profit by differentiating its product. But because there is free entry, new firms enter and compete the profit away, so in the long run firms earn only normal profit. Hairdressers, cafes and plumbers are typical examples: differentiated, numerous, and easy to enter.

Oligopoly and interdependence

Because of interdependence, prices tend to be stable: cutting price risks a price war (rivals match), and raising price risks losing customers (rivals do not follow). Firms therefore compete through non-price competition - advertising, branding, quality, loyalty schemes and product development. Firms may collude to act like a monopoly: overt collusion through a cartel that fixes prices or output, or tacit collusion such as price leadership. Cartels are illegal under competition law and unstable because each member has an incentive to cheat.

Price discrimination

Price discrimination raises the firm's profit and can fund services, but it reduces consumer surplus for the inelastic group and can be seen as unfair, so its overall effect is mixed.

Try this

Q1. State two features of an oligopoly. [2 marks]

  • Cue. A few large firms, high concentration, interdependence, barriers to entry, non-price competition (any two).

Q2. Explain why firms in monopolistic competition earn only normal profit in the long run. [4 marks]

  • Cue. Freedom of entry means new firms enter when supernormal profit exists, competing it away until only normal profit remains.

Q3. State the three conditions necessary for price discrimination. [3 marks]

  • Cue. Market power (price maker), different price elasticities of demand between groups, and the ability to separate markets and prevent resale.

Exam-style practice questions

Practice questions written in the style of CCEA exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.

CCEA A2 16 marksExplain, using the idea of interdependence, why firms in an oligopoly may avoid price competition.
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Worth 6 marks. Markers reward the meaning of interdependence and the reasoning that leads to price stability.

Interdependence: an oligopoly has a few large firms, so each firm's actions affect its rivals, and each must anticipate how rivals will react.

Risk of price cuts: if one firm cuts its price to win customers, rivals are likely to match the cut to protect their market share, so all firms end up with lower prices and lower profits and no one gains lasting sales.

Risk of price rises: if a firm raises its price, rivals may not follow, so it loses customers to them.

Conclusion: because both raising and cutting price tend to leave the firm worse off, prices tend to be stable, and firms compete instead through non-price methods such as advertising, branding and loyalty schemes.

CCEA A2 18 marksExamine the conditions necessary for a firm to operate successful price discrimination.
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Worth 8 marks. A strong answer states each condition, explains it, and evaluates with an example.

Market power: the firm must be a price maker, not a price taker, so it can set different prices rather than accept one market price.

Different elasticities: there must be groups of consumers with different price elasticities of demand, so the firm can charge a higher price to the inelastic group and a lower price to the elastic group.

No resale (separable markets): the firm must be able to keep the markets separate and stop buyers in the cheap market reselling to the dear market, otherwise arbitrage destroys the scheme.

Example: rail companies charge higher peak fares to inelastic commuters and lower off-peak fares to elastic leisure travellers, separated by time of travel.

Judgement: where all three conditions hold, price discrimination raises the firm's profit and can fund services, but it can be seen as unfair and reduces consumer surplus for the inelastic group, so its overall effect is mixed.

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