Monopolistic Competition

Characteristics of Monopolistic Competition:

1. Relatively large number of sellers
2. Differentiated products
3. Some control over price
4. Easy entry and exit (low barriers)
5. A lot of non-price competition (advertising)

Comparison: Monopoly vs. Perfect Competition Features

Key Contrast

Note: In monopolistic competition, long-run equilibrium yields zero profit but retains product differentiation and some market power.

Graph of Monopolistic Competition

Monopolistic Competition Earning a Economic Profit in the Short-Run

Firms in monopolistic competition were able to earn Economic Profit. However, in the Long-Run, new firms will enter, driving down the Demand for firms already in the market. Demand falls until there is no Economic Profit.

Monopolistic Competition Earning ZERO Economic Profit in the Long-Run

Monopolistic Competition and Excess Capacity

Firms can produce at a lower cost, but it holds back production to maximize profit.

Monopolistic Competition's Excess Capacity

Productive Efficiency and Allocative Efficiency

1. Short-Run Equilibrium

In the short run, a monopolistically competitive firm behaves exactly like a monopoly (due to a unique, differentiated product with no immediate substitutes).

Productive Efficiency in the Short Run

• Status: Not Productively Efficient (Generally).

• Explanation: The firm maximizes profit where MR=MCMR=MC. There is no competitive pressure forcing the firm to operate at the minimum of the Average Total Cost (ATC) curve. Depending on demand, the firm could be operating on the downward-sloping portion of the ATC (excess capacity) or even upward-sloping portion.

• Outcome: The firm is not required to minimize costs to survive in the short run.

Allocative Efficiency in the Short Run

• Status: Not Allocatively Efficient.

• Explanation: The profit-maximizing condition is MR=MCMR=MC. Because the demand curve is downward sloping, Price (PP) is greater than Marginal Revenue (MRMR). Therefore, at the output level produced, P>MCP>MC.

• Outcome: The value consumers place on the last unit exceeds the cost of producing it. Society would benefit from more output, creating Deadweight Loss.

2. Long Run Equilibrium

In the long run, free entry and exit drives economic profit to zero (Economic Profit=0Economic Profit=0).

Productive Efficiency in the Long Run

• Status: Not Productively Efficient (The defining feature of this market structure).

• Explanation: Entry of new firms shifts the individual firm's demand curve left and makes it more elastic. Equilibrium occurs where the demand curve is tangent to the ATC curve (so P=ATCP=ATC).

• Crucial Detail: Because the demand curve is downward sloping, this tangency must occur on the declining portion of the ATC curve. It cannot be at the minimum point (which is flat/horizontal).

• Result: The firm operates with Excess Capacity. They produce an output (QLRQLR​) that is less than the minimum efficient scale (QminATCQminATC​).

Allocative Efficiency in the Long Run

- Status: Not Allocatively Efficient.

• Explanation: Even with zero economic profit, the firm still produces where MR=MCMR=MC. At the tangency point (P=ATCP=ATC), it remains true that P>MRP>MR (due to the downward slope). Since MR=MCMR=MC, it follows that P>MCP>MC.

• Result: The markup (P−MCP−MC) persists. The market still fails to produce the quantity where the marginal benefit equals marginal cost.

3. Summary Table: Monopolistic Competition

相关笔记

Imperfect Competition
Monopoly
Oligopoly
Comparison Table of The 5 Market Structure