Monopolistic competition is a market structure characterized by many firms selling differentiated products, where there are low barriers to entry and exit.
Topic Synopsis
Monopolistic competition is a market structure characterized by many firms selling differentiated products, where there are low barriers to entry and exit. Firms have some degree of market power due to product differentiation, allowing them to be price makers in the short run, but they earn only normal profits in the long run due to the entry of new firms.
Key Concepts & Core Principles
- Product differentiation: Firms produce goods that are similar but not identical, allowing them to have some price-setting power. This can be real (e.g., quality differences) or perceived (e.g., branding).
- Short-run supernormal profit: In the short run, a firm can earn supernormal profit because its differentiated product gives it market power. The profit-maximising output is where MR = MC, and price is set on the AR curve.
- Long-run normal profit: Due to low barriers to entry, new firms enter the market attracted by supernormal profits. This shifts the demand curve for existing firms leftwards until only normal profit is earned (AR = AC at the profit-maximising output).
- Excess capacity: In long-run equilibrium, firms produce at an output below the minimum efficient scale (MES), meaning they have spare capacity. This is a source of productive inefficiency.
- Non-price competition: Firms compete through advertising, branding, product quality, and customer service rather than price, as price wars can erode profits.
Exam Tips & Revision Strategies
- Ensure diagrams clearly show the downward-sloping demand curve (AR) and marginal revenue (MR) curve, reflecting the firm's price-making power.
- Distinguish clearly between the short-run position (where supernormal profit is possible) and the long-run position (where entry of new firms shifts the demand curve left until only normal profit remains).
- Be prepared to evaluate the trade-off between the benefits of product variety and the lack of productive and allocative efficiency compared to perfect competition.
Examiner Marking Points
- Characteristics of monopolistic competition
- Short run equilibrium: supernormal profit or loss
- Long run equilibrium: normal profits
- Equilibrium price and output determination
- Advantages and disadvantages of monopolistic competition