Monopoly Economics: Chapter 15

The Nature and Origins of Monopoly

  • Definition of Monopoly: A firm that acts as the sole seller of a product for which there are no close substitutes. Unlike a competitive firm, a monopoly is a "price maker" and possesses market power, allowing it to alter the relationship between its costs and the selling price.

  • Core Characteristics:

    • One producer.

    • Market power to set prices.

    • Charges a price (PP) that exceeds marginal cost (MCMC).

    • High prices typically reduce the quantity purchased by consumers.

    • The resulting outcome is often not the socially optimal best for society.

  • Fundamental Cause: Barriers to Entry: A monopoly remains the sole seller because other firms cannot enter the market and compete. There are three primary sources of these barriers:

    1. Monopoly Resources: A key resource required for production is owned exclusively by a single firm. This allows the firm to charge much higher prices regardless of the cost of production. An example quote: "Rather than a monopoly, we like to consider ourselves ‘the only game in town’."

    2. Government Regulation: The government grants a single firm the exclusive right to produce a good or service. Common examples include:

      • Patents: Protection for pharmaceutical drugs to incentivize research.

      • Copyright Laws: Protection for authors and artists.

      • These laws lead to higher prices and higher profits for the producer to reward innovation.

    3. The Production Process (Natural Monopoly): A single firm can supply a good or service to an entire market at a lower average total cost than if two or more firms were competing. This is characterized by Economies of Scale over the relevant range of output (QQ).

      • Club Goods: These are goods that are excludable (you can prevent people from using them) but not rival in consumption (one person's use doesn't diminish another's). Natural monopolies often provide these.

      • ATC Dynamics: When production is divided among more firms, each produces less, causing the average total cost (ATCATC) to rise. Therefore, a single firm is most cost-efficient.

Production and Pricing Decisions for Monopolies

  • Competitive Firm vs. Monopoly Firm Demand:

    • Competitive Firm: Is a price taker. It faces a horizontal demand curve at the market price (PP). It can sell as much as it wants at this price.

    • Monopoly Firm: Is a price maker and the sole producer. It faces the downward-sloping market demand curve. To sell a higher quantity, the monopoly must accept a lower price.

  • Monopoly Revenue Concepts:

    • Total Revenue (TRTR): Calculated as price times quantity: TR=P×QTR = P \times Q.

    • Average Revenue (ARAR): Revenue per unit sold. Calculated as AR=TRQAR = \frac{TR}{Q}. This always equals the price (PP).

    • Marginal Revenue (MRMR): The revenue received for each additional unit of output. It is the change in total revenue when output increases by 1 unit (MR=ΔTRΔQMR = \frac{\Delta TR}{\Delta Q}).

  • The Relationship between Price and Marginal Revenue:

    • For a monopoly, MR < P (except for the first unit).

    • To increase the amount sold, the firm must lower the price charged to all customers. This leads to two effects on total revenue:

      1. The Output Effect: QQ is higher, which tends to increase TRTR.

      2. The Price Effect: PP is lower, which tends to decrease TRTR.

    • Marginal revenue can even become negative if the price effect outweighs the output effect.

  • Data Analysis from Table 1 (Monopoly Revenue for Water):

    • 0 gallons0\,gallons: P = $11, TR = $0, AR=(none)AR = (none), MR=(none)MR = (none).

    • 1 gallon1\,gallon: P = $10, TR = $10, AR = $10, MR = $10.

    • 2 gallons2\,gallons: P = $9, TR = $18, AR = $9, MR = $8.

    • 3 gallons3\,gallons: P = $8, TR = $24, AR = $8, MR = $6.

    • 4 gallons4\,gallons: P = $7, TR = $28, AR = $7, MR = $4.

    • 5 gallons5\,gallons: P = $6, TR = $30, AR = $6, MR = $2.

    • 6 gallons6\,gallons: P = $5, TR = $30, AR = $5, MR=0MR = 0.

    • 7 gallons7\,gallons: P = $4, TR = $28, AR = $4, MR=−2MR = -2.

    • 8 gallons8\,gallons: P = $3, TR = $24, AR = $3, MR=−4MR = -4.

  • Profit Maximization Rule:

    • The firm maximizes profit by producing the quantity where marginal revenue equals marginal cost: MR=MCMR = MC.

    • If MR > MC, the firm should increase production.

    • If MC > MR, the firm should decrease production.

    • The Price for this quantity is found on the demand curve (not the MRMR curve).

  • Comparison of Profit Maximization:

    • Perfect Competition: P=MR=MCP = MR = MC. Price equals marginal cost.

    • Monopoly: P > MR = MC. Price exceeds marginal cost.

  • Measuring Monopoly Profit:

    • Profit=TR−TCProfit = TR - TC

    • Profit=(P×Q)−(ATC×Q)Profit = (P \times Q) - (ATC \times Q)

    • Profit=(P−ATC)×QProfit = (P - ATC) \times Q

The Welfare Cost of Monopolies

  • Welfare Foundations:

    • Total Surplus: The sum of consumer surplus and producer surplus.

    • Consumer Surplus: The willingness to pay minus the amount paid.

    • Producer Surplus: The amount received minus the cost of production.

  • The Socially Efficient Level of Output: A benevolent social planner would choose the production level where the marginal cost curve intersects the demand curve. At this point, the value to buyers equals the cost to the producer. The efficient price is P=MCP = MC.

  • Monopoly Inefficiency:

    • The monopolist produces the quantity where MR=MCMR = MC, which is lower than the socially efficient quantity.

    • The monopolist charges a price (P > MC) higher than the efficient price.

    • Deadweight Loss (DWLDWL): Represented as the triangle between the demand curve and the marginal cost curve, showing the loss in total surplus due to the inefficiently low production level.

  • The Profit Myth: A monopoly's high profit is not necessarily a reduction in total economic welfare. While it increases producer surplus and decreases consumer surplus, the only true social loss is the deadweight loss caused by the inefficient quantity of output.

Price Discrimination

  • Definition: The business practice of selling the same good at different prices to different customers based on their willingness to pay.

  • Key Requirements and Implications:

    • It is a rational strategy to increase profit.

    • It requires the firm's ability to separate customers based on their willingness to pay.

    • It can potentially raise economic welfare compared to a single-price monopoly.

  • Perfect Price Discrimination: The firm charges each customer exactly their willingness to pay.

    • The monopoly captures the entire total surplus as profit.

    • There is no deadweight loss because the efficient quantity is produced.

    • Consumer surplus is zero.

  • Real-World Examples:

    • Movie Tickets: Lower prices for children and seniors who have lower willingness to pay.

    • Airline Prices: Lower prices for round-trip flights with Saturday night stays (separating business travelers from leisure travelers).

    • Discount Coupons: Only customers with a lower opportunity cost of time (and usually lower willingness to pay) will clip them.

    • Financial Aid: High tuition is the base price; need-based aid lowers the price for those with lower willingness to pay.

    • Quantity Discounts: Charging more for the first unit than for subsequent units (e.g., "Buy one, get one half off").

Public Policy Toward Monopolies

  1. Increasing Competition with Antitrust Laws:

    • Sherman Antitrust Act (1890): Designed to reduce the market power of large trusts.

    • Clayton Antitrust Act (1914): Strengthened the government's power to prevent anti-competitive practices.

    • Actions: Government can prevent mergers, break up conglomerates, and prevent price-coordination.

  2. Regulation:

    • Common for natural monopolies (utilities).

    • Government sets the price the monopolist is allowed to charge.

    • Marginal-Cost Pricing Issue: If the regulator sets P=MCP = MC, natural monopolies with declining ATCATC will have MC < ATC, resulting in losses for the firm. Additionally, firms have no incentive to reduce costs if prices are tied to costs.

  3. Public Ownership:

    • Example: US Postal Service.

    • The government operates the monopoly. The difference lies in incentives: private owners want to minimize costs for profit; public owners (bureaucrats) may lead to inefficiency, with taxpayers bearing the loss.

  4. Do Nothing:

    • Some economists argue the costs of government intervention (political failure) are often higher than the costs of market failure (monopoly pricing). Determining the role of government requires both political and economic judgment.

Questions & Discussion

  • Expert Discussion on Airline Mergers: Experts were asked if regulators should have approved major networked airline mergers in the past decade. The experts discussed whether travelers would be better off today if those mergers had been blocked.

  • Humor in High Finance: A quote about a merger illustrates the mindset of large corporations: "But if we do merge with Amalgamated, we’ll have enough resources to fight the anti-trust violation caused by the merger."

Comparative Summary: Competition vs. Monopoly

  • Similarities:

    • Goal of firms: Maximize profits.

    • Rule for maximization: MR=MCMR = MC.

    • Ability to earn economic profits: Possible in the short run for competition; possible in the long run for monopoly.

  • Differences:

    • Number of Firms: Many in competition; one in monopoly.

    • Marginal Revenue: MR=PMR = P in competition; MR < P in monopoly.

    • Price: P=MCP = MC in competition; P > MC in monopoly.

    • Quantity Produced: Produces socially efficient level in competition; produces less than socially efficient level in monopoly.

    • Entry in Long Run: Possible in competition; not possible (barriers) in monopoly.