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M08.L03 — Oligopoly: Characteristics and the Interdependence Problem

Module: Module 08 — Game Theory and Oligopoly Lesson: L03 of 05 Duration: ~30 minutes Level: Introductory Provenance: OpenStax Principles of Microeconomics 3e | Khan Academy Microeconomics

Learning Objective

Describe how oligopolies balance competition and interdependence.

Oligopoly Definition

An oligopoly is a market dominated by a few large firms (e.g., Australia's "Big 4" banks: CBA, Westpac, NAB, ANZ). Key traits: - High barriers to entry (e.g., regulations, economies of scale). - Strategic interdependence (firms react to rivals' actions). - Product differentiation (e.g., brand loyalty in airlines like Qantas vs. Virgin).

The Kinked Demand Curve Model

Explains price rigidity: - If Firm A raises prices, rivals don’t follow → demand drops sharply. - If Firm A lowers prices, rivals match → demand rises slightly. Result: Prices "stick" at the kink to avoid profit losses.

Worked Example: Australian Supermarkets

Scenario: Coles considers a 10% price cut on milk. 1. If Woolworths ignores: Coles gains market share. 2. If Woolworths matches: Minimal gain for Coles, profits drop for both. 3. Likely outcome: Woolworths matches → prices remain stable (kinked demand).

Common Misconception

"Oligopolies always collude to exploit consumers."

While collusion is illegal, tacit coordination (e.g., price leadership) can arise without explicit agreements.

Key Takeaways

  • Oligopolies feature mutual dependence among few firms.
  • The kinked demand curve explains price stability.
  • Collusion is illegal but tacit coordination occurs.
  • Australian examples include banking, airlines, and supermarkets.

Practice

  1. Why might an oligopoly avoid price wars?
  2. How do barriers to entry sustain oligopolies?
  3. Compare Qantas and Virgin Australia’s pricing strategies.

Further Resources

Provenance: OpenStax Principles of Microeconomics 3e | Khan Academy Microeconomics