Comparison Table of The 5 Market Structure
| Characteristic | Perfect Competition | Monopolistic Competition | Oligopoly | Simple Monopoly (No Price Discrimination) | Price-Discriminating Monopoly |
|---|---|---|---|---|---|
| Number of Firms | Very many | Many | Few | One | One |
| Product Type | Homogeneous | Differentiated | Homogeneous or Differentiated | Unique | Unique |
| Barriers to Entry | None | Low | High | Very high | Very high |
| Price Control | None (price taker) | Some, limited | Considerable (interdependent) | Significant (price maker) | Significant (multiple prices) |
| Pricing Strategy | Single market price | Single price (differentiated) | Interdependent pricing | Single price | Different prices to different consumers/units |
| Demand Curve Faced | Horizontal | Downward sloping, elastic | Downward sloping (kinked) | Downward sloping (market) | Downward sloping (but captures CS) |
| Long-Run Economic Profit | Zero (normal) | Zero (normal) | Positive possible | Positive possible | Positive (often higher than simple monopoly) |
| Deadweight Loss (DWL) | None | Yes (some) | Yes (significant) | Yes (largest among non-discriminating) | None (1st-degree) or Reduced (3rd-degree) |
| Allocative Efficiency (P = MC) | Yes | No (P > MC) | Usually no (P > MC) | No (P > MC) | Yes (1st-degree) on last unit; partial for 3rd-degree |
| Productive Efficiency (min ATC) | Yes | No (excess capacity) | Usually no | No (inefficient scale) | No (still produces above min ATC typically) |
| Consumer Surplus | Maximum | Reduced | Reduced | Very low | Zero (1st-degree) or partially captured |
| Examples | Wheat, corn | Restaurants, salons | Airlines, autos | Local water utility (unregulated) | Airline seats, student discounts, auctions |
相关笔记
Perfect Competition
Monopolistic Competition
Oligopoly
Monopoly
Price Discrimination