The Performance of Firms in Oligopolies (Cambridge International A-Level Economics)

Characteristics of Oligopoly

• Most imperfectly competitive industries operate in an oligopoly market structure

  • E.g., Banks, insurance companies, department stores, supermarkets, petrol retailers, sport stores etc.

Characteristics of an Oligopoly Market

Calculation of concentration ratios

• The most commonly used concentration ratios in the UK are the five-firm, ten-firm, and twenty-firm concentration ratios

• A five-firm concentration ratio of around 60% is considered to be an oligopoly

• A one-firm concentration ratio of 100% would be a pure monopoly

  • The UK Competition and Markets Authority (CMA) defines a monopoly as a firm with more than 25% market share

    • It prevents mergers or acquisitions from taking place which would give one firm more than 25% market share

Worked Example

Worked Example

The following table shows the value of UK Supermarket sales for the 3 months to the 31st March 2022.

Company	Value of Sales (£ million)
Tesco	136.5
Morrisons	55
The Co-operative	30
Sainsbury's	75
Aldi	44
Waitrose	24
Asda	77.5
Lidl	33
Iceland	15
Others	10
	500

Calculate the five-firm concentration ratio. Show your working.

Step 1: Identify the top five firms by value of sales and add the value of their sales together

Tesco (136.5) + Asda (77.5) + Sainsbury's (75) + Morrisons (55) + Aldi (44)

equals space 136.5 plus 77.5 plus 75 plus 55 plus 44 equals space £ 388 space million

Step 2: Calculate the percentage of total sales that the top five firms have

$\frac{388}{500} \times 100$

CR 5 equals space 77.6 percent sign

Collusive and non-collusive behaviour

Reasons for collusive and non-collusive behaviour

• Collusive behaviour in oligopolies occurs when firms cooperate to fix prices and restrict output

  • They cease to compete as vigorously as they can

• Non collusive behaviour in oligopolies occurs when firms actively compete to maintain/increase market share

Reasons for collusion

Types of collusion

• Collusion can be overt or tacit
• The net effect of collusion is that a group of firms end up acting like a monopoly in the market

Overt collusion

• Occurs when firms explicitly agree to limit competition or raise prices (price fixing)

• A cartel is the most restrictive form of collusion and is illegal in most countries

• The consequences of overt collusion include:

  • Higher prices for consumers
  • Less output in the market
  • Poor quality products and/or customer service
  • Less investment in innovation

• Overt collusion often happens in the following ways

  • Price fixing
  • Setting output quotas which limit supply and naturally results in price increases
  • Agreements to block new firms from entering the industry
  • Agreements to pay suppliers the same price thereby driving down prices in the supply chain (monopsony power)

Tacit collusion

• Occurs when firms avoid formal agreements but closely monitor each other's behaviour usually following the lead of the largest firm in the industry

• The most common form of tacit collusion is price leadership or price matching

  • This occurs when firms monitor the price of the largest firm in the industry and then adjust their prices to match
  • It is difficult for regulators to prove that collusion has occurred
  • It provides similar benefits to firms as overt collusion, but perhaps not to the same degree
  • It has similar consequences for consumers as overt collusion, but perhaps not to the same degree

Game theory

• Game theory is a mathematical framework which is used by firms to ensure optimal decisions are made in a strategic setting where there is a high level of interdependence (such as in oligopoly markets)

• Any game has three elements

  • The players - (firms)
  • The strategies available to the players
  • The payoffs (outcomes) that each player receives for each combination of strategies

• It was first illustrated using a simple model called The Prisoners Dilemma

  • Two criminals are caught after a train robbery (Carol and Doug)

    • The prosecutor does not have much evidence
    • The criminals are guilty but have agreed with each other that they will deny all involvement
    • The prosector wants one (or both) to confess

  • The strategies and payoffs available to the prisoners are presented in a payoff matrix

A prisoner's dilemma payoff matrix which illustrates game theory

Diagram analysis

• If Carol and Doug stick to their plan and deny involvement, they each get 3 years jail time

• If Doug confesses and indicates Carol's involvement, then Doug gets a lenient sentence of 1 year and Carol gets 10 years

• If Carol confesses and indicates Doug's involvement, then Carol gets a lenient sentence of 1 year and Doug gets 10 years

• There is a strong incentive to collude as it will yield the most beneficial outcome for Carol and Doug (3 years each)

• Fearing the worst, both players decide to confess and receive 5 years each

  • This outcome is called the dominant strategy as it carries the least risk

How firms use game theory

• Firms typically use game theory in the following situations:

  • When making decisions to raise or lower prices
  • When making decisions about new advertising and branding initiatives
  • When making decisions about investment in product innovation
  • When making decisions on product bundling e.g. combined phone and broadband package

• Below is a payoff matrix representing the strategic options available to Burger King and McDonald's when making advertising decisions

  • The £ payoffs represent the likely profits for each combination of choices selected

A payoff matrix which illustrates the strategies and payoffs available to firms when they are deciding to advertise or not to advertise

Diagram analysis

• If Burger King and McDonald's collude and agree not to advertise (top left), they can each enjoy £3 bn. in profits

  • There is a strong incentive to collude

• If Burger King advertises and McDonald's does not, then Burger King's profits are £5 bn. and McDonald's are £1 bn.

• If McDonald's advertises and Burger King does not, then McDonald's profits are £5 bn. and Burger King's are £1 bn.

• Both firms decide to advertise and receive £2 bn. of profits each

  • This outcome is called the dominant strategy as it carries the least risk
  • The risk of collusion is that one player will cheat and by doing so, get ahead

Worked Example The grid below shows the possible pricing strategies of two coffee companies. The Bean and Black Gold. Assuming that demand is price inelastic.

	The Bean: High	The Bean: Low
Black Gold: High	A	B
Black Gold: Low	C	D

Which of the following strategies in the grid would maximise the revenue of the two firms? Explain your answer.

Step 1: Use the information provided to select the correct option

A

Step 2: Explain your answer using economic knowledge

With reference to the revenue rule, firms whose demand is price inelastic should raise price to increase total revenue. When price rises and demand is inelastic, the percentage fall in quantity demanded is smaller than the percentage increase in price, so total revenue increases.

Therefore, the strategy that maximises the joint revenue of the two firms is A, where both firms charge a high price.

If one firm lowered its price while the other kept prices high (B or C), the price reduction would reduce revenue because demand is price inelastic.

Price competition

• Firms in an oligopoly market engage in three types of price competition

1. Price wars: occur when competitors repeatedly lower prices to undercut each other in an attempt to gain or increase market share. This often occurs when there is a lower level of non-price competition and where firms find it difficult to collude (either formal or tacit)
2. Predatory pricing: this is the practice of lowering prices when a new competitor joins the industry in order to drive them out. Prices are often lowered to a point below the cost of production. Once they have left the market, prices are raised again. This pricing strategy is usually illegal as it is anti-competitive
3. Limit pricing: occurs when firms set a limit on how high the price will go in the industry. A lower price reduces profit and disincentivize other firms from joining the industry. The greater the barriers to entry the higher the limit price is likely to be as firms are already disincentivized

Types of non-price Competition

• Firms engage in a wide range of non-price competition strategies

  • The aim is to increase product differentiation, develop or increase brand loyalty, and to increase market share

Strategies used in non-price competition