Market Structure

Marginal Revenue

• Marginal revenue involves a trade-off: lowering prices to sell more units reduces revenue per unit.
• Output effect: Revenue gained from selling more units. $Output \ effect = P \times \Delta Q$
• Discount effect: Revenue lost from price cuts on all units sold. $Discount \ effect = \Delta P \times Q$
• Marginal revenue is the balance of these effects: $Marginal \ revenue = Output \ effect - Discount \ effect$

Insights on Demand and Marginal Revenue

• Demand curve is downward-sloping: raising prices leads to customer loss.
• Marginal revenue curve is below the demand curve due to the discount effect.
• Marginal revenue curve declines more sharply than the demand curve; the discount effect increases with quantity.

Rational Rule for Sellers

• Produce until marginal revenue (MR) equals marginal cost (MC).
• Set price based on the demand curve to match customer willingness to pay.

Determining Quantity and Price Graphically

• Find the quantity where the marginal revenue curve intersects the marginal cost curve.
• Set the price at that quantity based on the demand curve.

Numerical Determination of Quantity and Price

• Calculate quantity and price where marginal revenue equals marginal cost to maximize profit.

Market Power and Price Setting

• Market power enables firms to set prices.
• Demand curve illustrates market power; a steeper curve indicates more power.
• To find firm’s quantity and price, produce where $MR = MC$ and set the price based on the demand curve.

Impact of Market Power

• Market power leads to worse outcomes, including higher prices and inefficiently smaller quantities.
• Increasing competition leads to better outcomes.

Outcomes of Market Power

• Higher prices: Firms charge above marginal costs.
• Smaller quantity: Higher prices reduce demand, leading to underproduction.
• Larger economic profits: Market power price exceeds average cost.
• Survival despite inefficiency: Less pressure to cut costs due to high profitability.

Policies to Encourage Competition

• Anti-collusion laws: Prevent agreements to limit competition.
• Merger laws: Prevent consolidation of market power through mergers.
• Illegal to Attempt to Monopolize: Prevent exclusionary practices.
• Encouraging international trade: Increases competition.

Policies to Minimize Harm from Market Power

• Price ceilings: Limit high prices.
• Government intervention: Regulations and subsidies for natural monopolies.

Government Regulation

• Ensure competition.
• Minimize the exploitation of market power through price ceilings and regulations on natural monopolies.

Business Decisions and Market Power

• Incumbent businesses benefit from market power; consumers and new businesses benefit from competition.
• As an entrepreneur, it's beneficial to enter markets with fewer competitors.