Skip to topic
    ← Back to course topics

    Oligopoly — OCR A-Level Economics

    Test yourself on Oligopoly with OCR A-Level practice questions.

    Start free

    7 days Premium · Then free forever · No card, no charge

    Oligopoly explained

    Oligopoly is a market structure characterized by a small number of large firms dominating the market, where firms are interdependent and often engage in non-price competition, product differentiation, and various forms of collusion.

    What to demonstrate

    1. Characteristics of oligopoly
    2. Non-price competition
    3. Interdependence and the kinked demand curve
    Show all 7 objectives
    1. Types of collusion
    2. Product differentiation
    3. Concentration ratios
    4. Advantages and disadvantages of oligopoly markets

    Oligopoly exam tips

    Topic Overview

    Oligopoly is a market structure characterised by a small number of large firms that dominate the market, leading to strategic interdependence. Unlike perfect competition or monopoly, firms in an oligopoly must consider the likely reactions of their rivals when making decisions about price, output, advertising, or product differentiation. This interdependence is the defining feature of oligopoly and gives rise to a range of possible outcomes, from collusive behaviour (where firms act together to maximise joint profits) to intense non-price competition. The study of oligopoly is crucial for understanding real-world markets such as banking, supermarkets, mobile networks, and airlines, where a few firms hold significant market power.

    In the OCR A-Level Economics specification, oligopoly is a key topic within the 'Microeconomics' component. You will need to understand the characteristics of oligopoly, including high barriers to entry, product differentiation, and the importance of non-price competition. The kinked demand curve model is a traditional tool used to explain price rigidity in oligopolistic markets, while game theory, particularly the prisoner's dilemma, provides insights into strategic decision-making and the tension between cooperation and self-interest. You should also be able to evaluate the pros and cons of oligopoly for consumers and the economy, including the potential for collusion (both overt and tacit) and the role of competition policy.

    Mastering oligopoly is essential because it bridges the gap between theoretical models and real-world market behaviour. It allows you to analyse why prices in some industries remain stable for long periods, why firms engage in heavy advertising and branding, and why governments intervene to prevent anti-competitive practices. This topic also develops your ability to think strategically and apply game theory to economic situations, skills that are highly valued in both exams and further study.

    Key Concepts
    • →Strategic interdependence: Firms' decisions are mutually dependent; each firm must anticipate rivals' reactions to its actions.
    • →Kinked demand curve: A model explaining price rigidity in non-collusive oligopoly; firms face a more elastic demand for price increases and less elastic demand for price decreases.
    • →Game theory and the prisoner's dilemma: A framework for analysing strategic choices; shows why firms may choose not to cooperate even when it is in their collective interest.
    • →Collusion (overt and tacit): Overt collusion involves explicit agreements (e.g., cartels), while tacit collusion arises from firms implicitly coordinating without direct communication.
    • →Non-price competition: Firms compete on factors other than price, such as advertising, branding, product differentiation, and after-sales service.
    Marking Points
    • Characteristics of oligopoly
    • Non-price competition
    • Interdependence and the kinked demand curve
    • Types of collusion
    • Product differentiation
    • Concentration ratios
    • Advantages and disadvantages of oligopoly markets
    Examiner Tips
    • 💡Ensure you can evaluate and calculate concentration ratios.
    • 💡Be prepared to explain the kinked demand curve diagram to illustrate interdependence.
    • 💡Distinguish clearly between different types of collusion.
    • 💡Use diagrams where appropriate to support explanations of oligopolistic behaviour.
    • 💡When analysing oligopoly, always start by stating the key characteristics: few firms, high barriers to entry, interdependence, and product differentiation. Use real-world examples (e.g., supermarkets, mobile networks) to illustrate your points and show application.
    • 💡For the kinked demand curve, draw the diagram clearly, label the kink, and explain why the marginal revenue curve has a vertical gap. Link this to price rigidity and the fact that costs can change without altering the profit-maximising price.
    • 💡In game theory questions, set up a payoff matrix correctly and explain the dominant strategy and Nash equilibrium. Discuss why collusion is unstable due to the incentive to cheat, and refer to real-world examples like OPEC or the UK detergent market.
    Common Mistakes
    • Misconception: Oligopoly always leads to collusion. Correction: While collusion is possible, many oligopolies are non-collusive due to incentives to cheat, legal restrictions, and the prisoner's dilemma. The kinked demand curve model assumes no collusion.
    • Misconception: The kinked demand curve explains how prices are set. Correction: The model explains why prices are stable once set, but it does not explain how the initial price is determined. It assumes firms match price cuts but not price rises.
    • Misconception: Oligopoly is the same as monopoly. Correction: Oligopoly involves multiple firms with significant market power, whereas monopoly is a single seller. Oligopolistic firms face competition, albeit limited, and must consider rivals' actions.
    Frequently Asked Questions
    What is the difference between collusive and non-collusive oligopoly?
    In a collusive oligopoly, firms cooperate to set prices or output levels, often forming a cartel to maximise joint profits. This can be overt (explicit agreements) or tacit (implicit coordination). In a non-collusive oligopoly, firms act independently, leading to strategic rivalry and outcomes like price wars or non-price competition. The kinked demand curve model applies to non-collusive oligopolies, while game theory helps analyse both scenarios.
    Why do oligopolistic firms often engage in non-price competition rather than price competition?
    Oligopolistic firms avoid price competition because it can trigger a price war, reducing profits for all. Instead, they compete through advertising, branding, product differentiation, quality improvements, and customer service. Non-price competition allows firms to increase market share without directly cutting prices, and it creates brand loyalty, making demand less elastic. This is especially common in markets like supermarkets and mobile phones.
    How does the kinked demand curve model explain price rigidity in oligopoly?
    The kinked demand curve model assumes that if a firm raises its price, rivals will not follow, so demand becomes elastic and the firm loses market share. If it lowers price, rivals match the cut to avoid losing customers, so demand is inelastic. This creates a kink at the current price, with a vertical gap in the marginal revenue curve. As a result, changes in marginal cost within the gap do not affect the profit-maximising price, leading to price stability.
    What is the prisoner's dilemma and how does it relate to oligopoly?
    The prisoner's dilemma is a game theory scenario where two players each have a choice to cooperate or defect. The dominant strategy for each is to defect, leading to a worse outcome for both than if they had cooperated. In oligopoly, firms face a similar dilemma: they could collude to set high prices and earn high profits, but each has an incentive to cheat by lowering price to gain market share. The result is often a non-cooperative outcome with lower profits, illustrating why collusion is unstable.
    What are the advantages and disadvantages of oligopoly for consumers?
    Advantages include potential for innovation due to high profits, product differentiation giving consumers choice, and economies of scale leading to lower costs. Disadvantages include higher prices than under perfect competition, reduced consumer sovereignty, and the possibility of collusion harming consumer welfare. Non-price competition can also lead to excessive advertising costs passed on to consumers. The net effect depends on the degree of competition and regulation.
    How does the UK government regulate oligopolistic markets?
    The UK government uses competition policy to regulate oligopolies, enforced by the Competition and Markets Authority (CMA). This includes prohibiting anti-competitive agreements (e.g., cartels) under the Competition Act 1998, investigating mergers that could substantially lessen competition, and conducting market studies to address practices like tacit collusion or abuse of dominance. The goal is to promote competition, protect consumers, and ensure efficient markets.

    More OCR A-Level Economics topics

    See every OCR A-Level Economics topic

    Start free

    Cookies on MasteryMind

    Essential cookies keep you signed in.

    Analytics and advertising cookies stay off unless you accept.

    Read our Privacy Policy.