Pricing under Oligopoly (Cournot Model, Kinked Demand Curve Model)

In an oligopoly, a market is dominated by a few large firms, each of which has significant control over market prices. Pricing under oligopoly is influenced by the interdependence of firms; each firm’s pricing strategy depends on the anticipated reactions of competitors. Common pricing behaviors include collusion, where firms may agree to set prices collectively to maximize joint profits, and price rigidity, where firms are reluctant to change prices due to fears of competitive retaliation. Kinked demand curve models suggest prices remain stable as firms expect competitors to follow price decreases but not price increases, leading to a stable price level.

Features of Pricing under Oligopoly:

1. Interdependence

Firms in an oligopoly are interdependent, meaning the pricing and output decisions of one firm significantly affect the others. Each firm must consider the potential reactions of its competitors when setting prices. This interdependence often leads to strategic behavior, where firms anticipate and respond to rivals’ moves, making pricing decisions more complex than in competitive markets.

2. Price Rigidity

Price rigidity is a common feature in oligopoly markets. Firms often avoid changing prices frequently due to the risk of price wars or competitive retaliation. If one firm lowers its prices, others may follow suit, leading to decreased profitability for all. Conversely, firms may hesitate to raise prices for fear of losing market share. This results in relatively stable prices over time.

3. Kinked Demand Curve Model

The kinked demand curve model suggests that prices in an oligopoly are stable due to asymmetric responses to price changes. According to this model, if a firm raises its price, competitors may not follow, causing the firm to lose market share. However, if a firm lowers its price, competitors are likely to match the decrease, leading to only a small gain in market share. This creates a kink in the demand curve, leading to price rigidity.

4. Collusion and Cartels

In some oligopolistic markets, firms may engage in collusion, either explicitly or tacitly, to set prices collectively and maximize joint profits. This can take the form of formal cartels, where firms agree on pricing and output levels, or informal agreements where firms align their behavior to avoid price competition. Collusion can lead to higher prices and reduced consumer welfare.

5. Non–Price Competition

Given the price rigidity, firms in oligopoly often engage in non-price competition to gain market share. This includes strategies such as advertising, product differentiation, improved customer service, and loyalty programs. Non-price competition allows firms to attract consumers without altering prices, which helps maintain stable price levels.

6. Barriers to Entry

Oligopolistic markets often have high barriers to entry that prevent new firms from entering the market. These barriers can include high capital requirements, economies of scale, strong brand loyalty, and control over essential resources. High entry barriers help existing firms maintain market power and stability in pricing.

7. Price Leadership

In an oligopoly, price leadership occurs when one firm, typically the largest or most dominant, sets the price, and other firms follow suit. This firm, known as the price leader, establishes the prevailing market price, and other firms adjust their prices accordingly. Price leadership helps maintain price stability and coordination within the market.

8. Strategic Behavior

Oligopolistic firms engage in strategic behavior to maximize their market position. This can include tactics such as limit pricing (setting a low price to deter new entrants), predatory pricing (temporarily lowering prices to drive competitors out of the market), and price discrimination (charging different prices to different consumer segments). Strategic behavior aims to influence competitors’ actions and maintain a competitive edge.

Cournot Model

The Cournot model, developed by Augustin Cournot in 1838, is a fundamental economic model used to describe how firms in an oligopoly decide on the quantity of output to produce, given that they face a few competitors. The model assumes that firms compete on the basis of quantity rather than price and that each firm makes decisions based on the output levels of its rivals.

Key Features:

1. Quantity Competition:

Firms choose their output levels simultaneously and independently. Each firm’s decision affects the market price and, consequently, the profits of all firms in the market.

2. Reaction Functions:

Each firm has a reaction function that determines its optimal output given the output levels of its competitors. The reaction function reflects how each firm adjusts its production in response to changes in the quantity produced by other firms.

3. Nash Equilibrium:

The model reaches equilibrium when each firm produces a quantity such that no firm can improve its profit by unilaterally changing its output. In other words, each firm’s output decision is optimal given the output levels of the other firms, leading to a Nash equilibrium in quantities.

4. Market Price:

The market price is determined by the total quantity produced by all firms. As firms increase their output, the market price typically decreases due to the law of demand.

5. Assumptions:

   • Firms produce homogeneous products.
   • Firms do not collude and set output levels independently.
   • Each firm aims to maximize profit.
   • The model assumes linear demand and cost functions for simplicity.

Implications:

• In the Cournot model, firms end up producing less than the competitive quantity but more than the monopoly quantity, resulting in higher prices and lower total output compared to a perfectly competitive market.
• The equilibrium quantities and prices depend on the number of firms in the market. As more firms enter, the quantity produced by each firm decreases, and the market price approaches the competitive level.

Kinked Demand Curve Model:

The kinked demand curve model, proposed by Paul Sweezy in 1939, is used to explain price stability in oligopolistic markets. The model suggests that prices are stable because firms are reluctant to change them due to the expected reaction of their competitors.

Key Features:

1. Demand Curve with a Kink:

The model assumes that the demand curve faced by an individual firm has a distinct kink at the current price level. The kink occurs because firms believe that rivals will match any price decrease but not a price increase.

2. Price Rigidity:

Due to the kinked demand curve, firms experience a relatively inelastic demand if they raise prices (as competitors will not follow suit) and a more elastic demand if they lower prices (as competitors will match the price decrease). This results in price rigidity, where firms are hesitant to change prices.

3. Marginal Revenue Curve:

The marginal revenue (MR) curve corresponding to the kinked demand curve is discontinuous, with a gap where the MR curve has a vertical segment. This gap means that changes in costs do not lead to changes in price because the MR curve is flat in the range of the kink.

4. Equilibrium:

The equilibrium price is established at the kink point. Firms produce where their MR intersects with their marginal cost (MC), leading to stable prices despite changes in cost conditions.

5. Assumptions:

   • Firms produce homogeneous products.
   • There is a high degree of interdependence among firms.
   • Firms expect competitors to follow price decreases but not price increases.

Implications:

• The kinked demand curve model explains why prices in oligopolistic markets tend to be stable even in the face of fluctuating costs. Firms are reluctant to change prices due to the anticipated reactions from competitors.
• The model suggests that firms focus on non-price competition, such as advertising and product differentiation, to gain market share without altering prices.

Summary:

• Cournot Model: Focuses on quantity competition, where firms decide on output levels leading to a Nash equilibrium in quantities. It predicts higher prices and lower output than in competitive markets.
• Kinked Demand Curve Model: Explains price stability in oligopoly by suggesting that firms face a demand curve with a kink, leading to price rigidity due to expected reactions from competitors.