Monopoly

Introducing a New Market Structure

Monopoly is a distinct market structure where a single seller dominates the market, setting prices rather than taking them. Unlike perfectly competitive markets, monopolists are price-makers, possessing significant market power.

• Price Maker: A seller that can set the price of a good.

• Market Power: The ability to influence or set the price of a product.

• Monopoly: One seller of a good or service with no close substitutes.

• Perfect Competition: Firms are price-takers, unable to influence market price.

Sources of Market Power

Monopolies arise due to barriers to entry, which prevent potential competitors from entering the market. These barriers can be legal, natural, or based on control of key resources.

• Legal Market Power: Government-granted rights such as patents and copyrights.

• Natural Market Power: Occurs when a firm owns a key resource or enjoys economies of scale.

• Control of Key Resources: Exclusive access to essential materials (e.g., Alcoa's bauxite, De Beers' diamonds).

• Economies of Scale: Cost advantages due to large-scale production, leading to natural monopoly.

• Network Externalities: Product value increases as more consumers use it (e.g., Facebook, eBay).

The Monopolist’s Problem

Monopolists must understand production costs and how inputs combine to make outputs. Unlike perfect competitors, monopolists face a downward-sloping demand curve, meaning they must lower prices to sell more units.

• Demand Curve: Monopolists face the market demand curve, not a horizontal one.

• Marginal Revenue (MR): The additional revenue from selling one more unit; for monopolists, MR < Price.

• Quantity Effect: Selling more units increases revenue.

• Price Effect: Lowering price reduces revenue from previous units.

Example: If a monopolist sells 200 units at $5 each and lowers the price to $4 to sell 400 units, it gains revenue from extra units but loses revenue from the price drop on previous units.

Choosing the Optimal Quantity and Price

Monopolists maximize profit by equating marginal revenue and marginal cost, then setting price above marginal cost. Unlike competitive firms, monopolists do not have a supply curve.

• Profit Maximization Rule: Monopolist sets ; competitive firm sets .

• No Supply Curve: Monopolists are price-makers, so the supply relationship does not exist.

Formula:

(Monopolist chooses quantity where marginal revenue equals marginal cost)

(Monopolist sets price above marginal cost)

The “Broken” Invisible Hand: The Cost of Monopoly

Monopoly leads to inefficiency in the market, breaking the invisible hand mechanism. Consumer surplus decreases, producer surplus increases, and deadweight loss emerges.

• Consumer Surplus: Lower than in perfect competition.

• Producer Surplus: Higher for the monopolist.

• Deadweight Loss: Lost welfare due to reduced output and higher prices.

Restoring Efficiency

Monopolists may use price discrimination to increase efficiency and profits. Price discrimination involves charging different prices to different customers for the same product.

• First-Degree (Perfect) Price Discrimination: Each consumer pays their maximum willingness to pay.

• Second-Degree Price Discrimination: Prices vary based on purchase characteristics (e.g., bulk discounts).

• Third-Degree Price Discrimination: Prices vary based on customer characteristics (e.g., student discounts).

Government Policy Toward Monopoly

Governments regulate monopolies to prevent anti-competitive behavior and deadweight loss. Antitrust laws and price regulation are common tools.

• Antitrust Policy: Prevents anti-competitive pricing and market dominance.

• Sherman Act (1890): Prohibits monopolization and restraints on trade.

• Price Regulation: Sets prices equal to marginal cost (efficient) or average total cost (fair-return).

Evidence-Based Economics

Monopoly can sometimes benefit society by fostering innovation, especially in industries with strong competitors. Patents, for example, incentivize research and development.

• Innovation: Market power can encourage firms to innovate.

• Patent Example: Awarding a patent to Claritin creates monopoly power, affecting price, quantity, consumer surplus, and producer surplus.

Summary Table: Monopoly vs. Perfect Competition

Additional info: The Pearson logo is included as it is directly relevant to the publisher of the textbook, reinforcing the academic context of the notes.