Microeconomics 3: Market Structures

Analysis of competitive equilibrium, welfare theorems, and imperfect competition (monopoly and oligopoly). Second-year undergraduate course at the University of Bordeaux.

Term: First Semester

Course Overview

This course studies the relationship between market structure, firm strategy, and market efficiency. It builds on the competitive equilibrium framework introduced in Microeconomics 1 and 2 (L1) and extends it to imperfectly competitive markets. The course is designed by Prof. Pascale Roux.

Part I — Competitive Equilibrium and Welfare

  • Partial equilibrium review (short and long run)
  • General equilibrium under perfect competition
  • The two welfare theorems: efficiency and equilibrium

Part II — Monopoly

  • Classical monopoly and deadweight loss
  • Natural monopoly and regulation
  • Price discrimination (1st, 2nd, and 3rd degree)

Part III — Oligopoly

  • Cartels and collusion
  • Quantity competition: Cournot and Stackelberg models
  • Price competition: Bertrand model

Prerequisites

  • Consumer behaviour (utility maximisation, demand)
  • Producer behaviour (cost minimisation, supply)
  • Partial equilibrium under perfect competition (Microeconomics 1 & 2)

Assessment

Component Weight
Continuous assessment (mini-tests, common exam, oral participation) 60%
Final exam (exercises, problems, reflective questions) 40%

My Role

I taught the TD sessions (13.5 hours per group, 3 to 5 groups depending on the year) — practical problem-solving classes where students work through exercises on each topic covered in the lectures. The lectures (CM) are taught by the course professor, Pr. Pascale Roux.

Schedule

Week Date Topic Materials
1 Review: Partial Competitive Equilibrium

Short-run and long-run equilibrium under perfect competition. Review of consumer and producer behaviour.

2 General Equilibrium and Welfare

From partial to general equilibrium. The two welfare theorems and the conditions under which market equilibrium is efficient.

3 Monopoly — Classical Analysis

Profit maximisation under monopoly, deadweight loss, and comparison with the competitive benchmark.

4 Monopoly — Natural Monopoly and Regulation

Natural monopoly, regulatory approaches (marginal cost pricing, Ramsey pricing), and public ownership.

5 Price Discrimination

First, second, and third-degree price discrimination. Welfare effects and real-world examples.

6 Oligopoly — Cartels and Collusion

Joint profit maximisation, cartel stability, and competition policy.

7 Oligopoly — Cournot Competition

Quantity competition, Nash equilibrium in the Cournot model, and comparison with monopoly and perfect competition.

8 Oligopoly — Stackelberg Competition

Sequential quantity competition, first-mover advantage, and strategic commitment.

9 Oligopoly — Bertrand Competition (if time permits)

Price competition, the Bertrand paradox, and product differentiation as a resolution.