CHAPTEr 10:Monopoly and Price Discrimination: Key Concepts in Microeconomics

Monopoly and Price Discrimination

Definition and Characteristics of Monopoly

A monopoly is a market structure in which a single firm is the sole seller of a product with no close substitutes. The monopolist has significant control over the market price due to the absence of competition.

• Key Point 1: A monopoly exists when one firm dominates the market for a particular good or service.

• Key Point 2: The primary cause of monopoly is barriers to entry, which prevent other firms from entering the market.

• Example: Microsoft is considered to have a monopoly in the market for Windows operating systems.

Barriers to Entry

Barriers to entry are obstacles that make it difficult or impossible for new firms to enter a market and compete with the monopolist.

• Exclusive Rights: A firm may obtain exclusive rights from the government to produce a good or service.

• Examples:

  • Pharmaceutical companies can apply for a patent when they discover a new drug, granting them exclusive production rights.

  • A vendor may obtain a license to sell products in a restricted area, such as a national park or at a major event.

• Economies of Scale: When a single firm can supply the entire market at a lower cost than multiple firms, it is called a natural monopoly. Entry by additional firms would result in losses for all.

• Examples of Natural Monopolies: Cable TV service, water supply, and electricity generation.

The Monopolist’s Output and Price Decisions

Unlike firms in perfect competition, a monopolist can influence the market price by adjusting the quantity of output supplied. The monopolist aims to maximize profit by equating marginal revenue (MR) and marginal cost (MC).

• Key Point 1: The monopolist faces the entire market demand curve.

• Key Point 2: The monopolist’s marginal revenue (MR) curve is downward sloping and always less than the price. For example, at 75 units, MR = 15 and price = 30.

• Key Point 3: To sell more than 75 units, the monopolist must lower the price below $30.

• Key Point 4: The profit-maximizing output is where MR = MC. For example, at 100 units, MR = MC = 5 and market price = $25.

• Formula:

  • Profit Maximization Condition: $MR = MC$

Monopoly Versus Perfect Competition

Monopoly and perfect competition are two contrasting market structures. Their outcomes differ in terms of price, quantity, and efficiency.

• Monopoly Equilibrium:

  • Quantity = 100

  • Price = $25

• Perfect Competition Equilibrium:

  • Quantity = 200

  • Price = $5

• Key Point: Monopoly produces less output and charges a higher price compared to perfect competition.

Deadweight Loss from Monopoly

Deadweight loss is a measure of the inefficiency caused by monopoly. It represents the loss of total surplus (consumer and producer surplus) that occurs because the monopolist restricts output below the socially optimal level.

• Consumer Surplus under Perfect Competition: Area C + R + D

• Consumer Surplus under Monopoly: Area C

• Monopoly Profit: Area R

• Deadweight Loss: Area D

Additional info: In standard microeconomic diagrams, area D is the triangle between the demand and supply curves that is lost due to reduced output under monopoly.

Price Discrimination

Price discrimination occurs when a firm charges different prices to different consumers for the same product, based on their willingness to pay or other characteristics.

• Key Point 1: Firms engage in price discrimination to increase profits.

• Example: Airlines charge lower prices for tickets purchased in advance and higher prices for last-minute business travelers.

• Conditions for Price Discrimination:

  1. Market Power: The firm must be able to set its own price.

  2. Different Consumer Groups: Consumers must differ in their willingness to pay or price sensitivity.

  3. Resale is Not Possible: It must be impractical for consumers to resell the product to others.

• Profit Increase: Price discrimination allows firms to capture more consumer surplus as profit.

• Example: Students may pay $150 for a ticket, while business travelers pay $550 for the same ticket.

• Key Point: Consumers with greater willingness to pay or less elastic demand are charged higher prices.

Comparison Table: Monopoly vs. Perfect Competition

Market Structure	Quantity Produced	Price Charged	Efficiency
Monopoly	100	$25	Lower (deadweight loss)
Perfect Competition	200	$5	Higher (no deadweight loss)

Summary of Key Terms

• Monopoly: Sole seller, no close substitutes, barriers to entry.

• Barriers to Entry: Patents, licenses, economies of scale.

• Natural Monopoly: Arises from economies of scale.

• Marginal Revenue (MR): Additional revenue from selling one more unit.

• Marginal Cost (MC): Additional cost from producing one more unit.

• Deadweight Loss: Loss of total surplus due to monopoly pricing.

• Price Discrimination: Charging different prices to different consumers for the same product.