1. Monopolistic competition and Oligopoly
Unit 12
Monopolistic competition
and
Oligopoly

2. Outcomes Define and explain monopolistic competition
Define and explain oligopoly market structures
Define and explain price competition
Describe difference between competition and collusion
Discuss oligopolistic pricing

3. Monopolistic competition
Market in which firms can enter freely,
Each producing it’s own brand or version
Of a differentiated product.

4. Monopolistic competition
Two key characteristics:
Firms compete by selling differentiated products which is highly substitutable but not perfect substitutes.
There is free entry and exit.
When market is in equilibrium, firms are doing their best and have no reason to change their price or output

5. SR and LR equilibrium

6. Monopolistic competition and economic efficiency
Perfect competitive market are desirable because = economic efficient.
Monopolistic competition is similar.
Two source of inefficiency in monopolistic competition:
Equilibrium price > MC: Value exceeds cost
Output below minimizing average cost: Excess capacity is inefficient.

7. Monopolistic competition and economic efficiency
Inefficiencies make consumers worse off:
Should this market be regulated? No, why:
Monopoly power is small.
Important benefit: Product diversity. Consumers value to choose between a wide variety.

8. Monopolistic competition and economic efficiency

9. Oligopoly
Market in which only a few firms compete with one another, and entry by new firm is impeded.

10. Oligopoly Behaviour of other firms always taken into account.
Barriers to entry: Difficult or impossible for new firms to enter.
If just 2 firms = Duopoly
For our purpose, only focus on duopolies: One competitor to worry about.

11. Equilibrium in oligopoly
Equilibrium where MR=MC
Nash Equilibrium: Set of strategies or actions in which each firm does the best it can given its competitors’ action.
And so will the competitor do the best they can.

12. The Cournot model
Simple model of duopolies introduced by Augustin Cournot.
Firms produce homogenous goods
Know the market demand curve
Each firm must decide how much to produce
Two firms make their decision at the same time
Take competitor into account

13. Cournot model Essence of model:
Level of output for competitor fixed
When deciding how much to produce
Reaction curve: Relationship between a firm’s profit maximizing output and the amount it thinks its competitor will produce.
Cournot equilibrium: Each firm correctly assumes how much its competitor will produce and sets its own production level accordingly

14. Firm 1’s output decisions

15. The Cournot model

16. The Stackelberg model - First mover advantage
First assumed: Duopolist make output decision at the same time.
Stackelberg model: Oligopoly module in which one firm sets its output before other firms do.
See example page 455
Cournot and Stackleberg models are alternative representations of oligopolistic behaviors

17. Oligopoly: Setting the price - Price competition
Oligopolistic firms compete by setting quantities.
But, it can occur along price discrimination.
Nash equilibrium used to study price competition.
First in a industry producing homogeneous products,
Second, in a industry with some degree of product differentiation.

18. Price competition with homogeneous products
The Bertrand Model:
Oligopoly model
In which firms produce a homogenous good
Each firm treats the price of it’s competitors as fixed
All firms decide simultaneously what price to charge.

19. Bertrand model Firms choose price instead of quantity.
Will dramatically affect market outcome.
View example on page 458
Firm price at MC and make no profit!

20. Bertrand model Criticism: Useful:
More natural to compete by setting quantities rather than price, as with a homogeneous good.
If firms do set prices and choose the same price, what share of total sales will go to each one?
Useful:
Shows how equilibrium output in oligopolies can depend crucially on the firms’ choice of strategic variable.

21. Price competition with differentiated products
Some degree of product differentiation.
Example: Gas station differs in location and service provided.
Market share not only determined by price but also differences in:
Design
Performance
Durability
Natural for firm to compete on price!

22. Price competition with differentiated products
Simple example on page 458

23. Competition vs. Collusion: - The prisoner’s dilemma
Nash equilibrium = non-cooperative equilibrium:
Each firm makes the decisions that give it the highest possible profit,
given the actions of competitors
Non-cooperative game: Game in which negotiation and enforcement of binding contracts are not possible.
Collusion = Illegal: Coordinate prices and output levels to maximize joint profits = Cartel

24. Competition vs. Collusion: - The prisoner’s dilemma
Cooperation  higher profits: Why not cooperate without explicitly colluding?
Set a price and hope competitor set the same price!
Problem: Competitor will not choose to set price at same level. Will do better by setting lower price.
See example page 461

25. Competition vs. Collusion: - The prisoner’s dilemma
Table showing profit/payoff to each firm given its decision and decision of competitor
Game theory example in which 2 prisoners must decide separately whether to confess to a crime.
Confess = Lighter sentence and accomplice heaver sentence

26. Competition vs. Collusion: - The prisoner’s dilemma
Oligopolistic firm often find themselves in a prisoner’s dilemma.
Compete aggressively, gain market share, or
Compete passively, coexist with competitor and settle for market share.
Implicitly collude!

27. Implications of the prisoners’ dilemma for oligopolistic pricing
Firms price over and over again.
Continually observe competitors.
And adjust!
Competitors can develop mistrust if one firm ‘rocks the boat’ – by changing price or increase advertising.

28. Price rigidity Definition: Basis for the kinked demand curve model:
Firms are reluctant to change prices even if costs or demand change
Basis for the kinked demand curve model:
Oligopoly model
Each firm faced a demand curve kinked at prevailing price
At higher price demand is elastic and vice versa

29. Kinked demand curve

30. Price signaling and price leadership
Form of implicit collusion
Firm announces a price
Increase in the hope that other firms will follow suit
Price leadership:
Pattern of pricing
In which one firm
Regularly announces price changes
That other firms then match

31. The dominant firm model
Definition:
Firm with a large share of total sales
That sets price to maximize profits
Taking into account the supply response of smaller firms.

32. The dominant firm model

33. Cartels
Explicit agree to cooperate by setting price and output levels.
Often international – law poorly enforced.
OPEC cartel = international agreement.
Conditions for success:
Stable cartel organization must be formed, members agree on price and production levels, and must adhere to agreement.
Potential monopoly power.

34. Cartel