1. Chapter 13: Strategic Decision Making in Oligopoly Markets
McGraw-Hill/Irwin
Copyright © 2011 by the McGraw-Hill Companies, Inc. All rights reserved.

2. Oligopoly Markets Interdependence of firms’ profits
Distinguishing feature of oligopoly
Arises when number of firms in market is small enough that every firms’ price & output decisions affect demand & marginal revenue conditions of every other firm in market

3. Features of oligopoly Fewness of sellers Seller interdependence
Feasibility of coordinated action among ostensibly independent firms

4. Seller interdependence
If Kroger offers deep discounts on soft drinks, will Wal-Mart follow suit?
Verizon carries unused minutes over the to next month—implications for AT&T, et. al.?
If AA discounts fares on its Chicago to NY service, will United follow?
If Regions charges swipe fees, how will rival banks react?
How will Duracell react to an aggressive marketing campaign by EverReady?
Alcoa’s decision to add production capacity is conditioned upon the investment plans of rival aluminum producers.

5. Measures of seller concentration
The concentration ratio is the percentage of total market sales accounted for by an absolute number of the largest firms in the market.
The four-firm concentration ratio (CR4) measures the percent of total market sales accounted for by the top four firms in the market.
The eight-firm concentration ratio (CR4) measures the percent of total market sales accounted for by the top eight firms in the market.

6. Concentration Ratios: Very Concentrated Industries
Source: U.S. Bureau of the Census, Census of Manufacturers

7. Concentration Ratios: Less Concentrated Industries
Source: U.S. Bureau of the Census, Census of Manufacturers

8. Game Theory and Competitive Strategy
Selecting a course of action in a situation in which rival players are selecting strategies that suit their interests is the basic problem of game theory.

9. 1. Players and their actions
A situation of competitive rivalry must involve two or more players whose choice of actions affect each other.
A “player” can be a firm, an interest group or coalition, a military leader, government official.
Games generally consider only one kind of action—e.g., number of daily departures, fares, in-flight services, schedules, advertising, technology, choice of hubs, ordering planes, expanding terminals, use of computerized reservations systems, mergers and acquisitions, and human resource decisions.

10. 2. Outcomes and Payoffs
The firm’s action, together with the actions of its rivals, determine its payoff
In the standard “business” game, the payoff can be in the form of profit, market share, ratings points,
In war games, the payoff might be measured in enemy killed or territory seized.
In political games, payoffs may be measured in votes or campaign contributions.

11. 3. Underlying “rules”
The rules of the game define the range of possible outcomes and payoffs
For example, collusion to fix prices or a merger among direct rivals in a concentrated market structure may be against the rules.
Another set a rules specifies whether players move sequentially or simultaneously, who moves first, and what does each player know about the other players’ preference and prior to actions?

12. Strategic Decisions Strategic behavior Game theory
Actions taken by firms to plan for & react to competition from rival firms
Game theory
Useful guidelines on behavior for strategic situations involving interdependence
Simultaneous Decisions
Occur when managers must make individual decisions without knowing their rivals’ decisions

13. Dominant Strategies
Always provide best outcome no matter what decisions rivals make
When one exists, the rational decision maker always follows its dominant strategy
Predict rivals will follow their dominant strategies, if they exist
Dominant strategy equilibrium
Exists when all decision makers have dominant strategies

14. Prisoner’s dilemma
Bill and Jane have been charged with bank robbery. But lacking a confession,
the DA can only get a “reckless endangerment” charge to stick. So the police play one suspect off against the other.

15. Let’s make a deal
OK, Bill. Confess, give evidence on Jane, and you get a reduced sentence of one year in prison.

16. What will Jane do?
Bill

17. Prisoners’ Dilemma All rivals have dominant strategies
In dominant strategy equilibrium, all are worse off than if they had cooperated in making their decisions

18. Prisoners’ Dilemma (Table 13.1)
Bill
Don’t confess
Confess
Jane A
2 years, 2 years B
12 years, 1 year C
1 year, 12 years D
6 years, 6 years B J J B

19. Principle: When a firm does not have a dominant strategy but at least one of its rivals does have a dominant strategy, the firm can predict that its rivals will follow their dominant strategies. Thus the problem for the firm is to select the strategy that gives the highest payoff conditional upon rival pursuing their dominant strategies.

20. Dominated Strategy
A strategy is dominated if, regardless of what any other players do, the strategy earns a player a smaller payoff than some other strategy. Hence, a strategy is dominated if it is always better to play some other strategy, regardless of what opponents may do. If a player has a dominant strategy than all others are dominated, but the converse is not always true.

21. Dominated Strategies
Never the best strategy, so never would be chosen & should be eliminated
Successive elimination of dominated strategies should continue until none remain
Search for dominant strategies first, then dominated strategies
When neither form of strategic dominance exists, employ a different concept for making simultaneous decisions

22. Successive Elimination of Dominated Strategies (Table 13.3)
Pizza Pricing
Palace’s price
High ($10)
Medium ($8)
Low ($6)
Castle’s price
High
($10) A
$1,000, $1,000 B
$900, $1,100 C
$500, $1,200
Medium
($8) D
$1,100, $400 E
$800, $800 F
$450, $500
Low
($6) G
$1,200, $300 H
$500, $350 I
$400, $400 C C P P C P
Payoffs in dollars of profit per week

23. Successive Elimination of Dominated Strategies (Table 13.3)
Unique Solution
Reduced Payoff Table
Palace’s price
Medium ($8)
Low ($6)
Castle’s price
High
($10) B
$900, $1,100 C
$500, $1,200
Low
($6) H
$500, $350 I
$400, $400 C C P P
Payoffs in dollars of profit per week

24. Castle does not have a dominant strategy. But Palace does
Castle does not have a dominant strategy. But Palace does. Castle should select its best strategy, given Castle will pursue its dominant strategy

25. Making Mutually Best Decisions
For all firms in an oligopoly to be predicting correctly each others’ decisions:
All firms must be choosing individually best actions given the predicted actions of their rivals, which they can then believe are correctly predicted
Strategically astute managers look for mutually best decisions

26. Nash Equilibrium
Set of actions or decisions for which all managers are choosing their best actions given the actions they expect their rivals to choose
Strategic stability
No single firm can unilaterally make a different decision & do better

27. Nash decisions are likely to chosen because Nash sets of decisions are mutually best and thus, “strategically stable.” No player can do better by unilaterally changing its decision. Non-Nash decisions are unlikely to be chosen because at least one player can improve its payoff by changing its decision.
Beautiful Mind

28. Super Bowl Advertising: A Unique (Non-Cooperative) Nash Equilibrium
Note: No dominant or dominated strategies
Pepsi’s budget
Low
Medium
High
Coke’s budget A
$60, $45 B
$57.5, $50 C
$45, $35 D
$50, $35 E
$65, $30 F
$30, $25 G
$45, $10 H
$60, $20 I
$50, $40 C P P C C P
Payoffs in millions of dollars of semiannual profit

29. Why is High-High Stable?
Suppose Coke and Pepsi cooperate—Both choose “low” and maximize joint profit.
Pepsi can do better by unilaterally selecting “medium.”
In some cells, both Coke and Pepsi can increase their payoffs by changing strategies—Consider cell F, for example.

30. Nash Equilibrium
When a unique Nash equilibrium set of decisions exists
Rivals can be expected to make the decisions leading to the Nash equilibrium
With multiple Nash equilibria, no way to predict the likely outcome
All dominant strategy equilibria are also Nash equilibria
Nash equilibria can occur without dominant or dominated strategies

31. Best-Response Curves
Analyze & explain simultaneous decisions when choices are continuous (not discrete)
Indicate the best decision based on the decision the firm expects its rival will make
Usually the profit-maximizing decision
Nash equilibrium occurs where firms’ best-response curves intersect

32. Deriving Best-Response Curve for Arrow Airlines (Figure 13.1)
Arrow Airline’s price and marginal revenue
Panel A : Arrow believes PB = $100
Bravo Airway’s quantity
Arrow Airline’s price
Panel B: Two points on Arrow’s best-response curve
Bravo Airway’s price

33. Best-Response Curves & Nash Equilibrium (Figure 13.2)
Arrow Airline’s price
Bravo Airway’s price

34. Sequential Decisions
One firm makes its decision first, then a rival firm, knowing the action of the first firm, makes its decision
The best decision a manager makes today depends on how rivals respond tomorrow

35. Game Tree
Shows firms decisions as nodes with branches extending from the nodes
One branch for each action that can be taken at the node
Sequence of decisions proceeds from left to right until final payoffs are reached
Roll-back method (or backward induction)
Method of finding Nash solution by looking ahead to future decisions to reason back to the current best decision

36. Sequential Pizza Pricing
Panel B – Roll-back solution
Panel A – Game tree

37. First-Mover & Second-Mover Advantages
First-mover advantage
If letting rivals know what you are doing by going first in a sequential decision increases your payoff
Second-mover advantage
If reacting to a decision already made by a rival increases your payoff
Determine whether the order of decision making can be confer an advantage
Apply roll-back method to game trees for each possible sequence of decisions

38. Cellular Service in Brazil
Motorola
Sony
Annual cost of analog
$250
$400
Annual cost of digital
$350
$325
Use of incompatible technologies would reduce the market demand for cellular service.
Motorola would obviously prefer analog; Sony digital.
Brazilian government has imposed a price ceiling—technology is the decision variable.

39. First-Mover Advantage in Technology Choice
Motorola’s technology
Analog
Digital
Sony’s technology A
$10, $13.75 B
$8, $9 C
$9.50, $11 D
$11.875, $11.25 S M S M
Panel A – Simultaneous technology decision

40. To determine if a first mover advantage exists, construct a decision tree and then “roll back.”

41. First-Mover Advantage in Technology Choice
Panel B – Motorola secures a first-mover advantage

42. Strategic Moves & Commitments
Actions used to put rivals at a disadvantage
Three types
Commitments
Threats
Promises
Only credible strategic moves matter
Managers announce or demonstrate to rivals that they will bind themselves to take a particular action or make a specific decision
No matter what action is taken by rivals

43. Credible Moves
There is no doubt the strategic move will be carried out because it is in the best interest of the player making the move to carry it out.

44. The NBA Players Association made the decision to decertify its union and bring an anti-trust suit against the NBA owners. Whether this amounts to a credible strategic move is open to debate.

45. Threats & Promises Conditional statements Threats Promises
Explicit or tacit
“If you take action A, I will take action B, which is undesirable or costly to you.”
Promises
“If you take action A, I will take action B, which is desirable or rewarding to you.”

46. Cooperation in Repeated Strategic Decisions
Cooperation occurs when oligopoly firms make individual decisions that make every firm better off than they would be in a (noncooperative) Nash equilibrium

47. Cheating Making noncooperative decisions One-time prisoners’ dilemmas
Does not imply that firms have made any agreement to cooperate
One-time prisoners’ dilemmas
Cooperation is not strategically stable
No future consequences from cheating, so both firms expect the other to cheat
Cheating is best response for each

48. Pricing Dilemma for AMD & Intel
AMD’s price
High
Low
Intel’s price A:
$5, $2.5 B:
$2, $3 C:
$6, $0.5 D:
$3, $1
Cooperation
AMD cheats
Intel cheats A
Noncooperation I I A
Payoffs in millions of dollars of profit per week

49. Punishment for Cheating
With repeated decisions, cheaters can be punished
When credible threats of punishment in later rounds of decision making exist
Strategically astute managers can sometimes achieve cooperation in prisoners’ dilemmas

50. In a one-time game, there is no opportunity to punish cheaters
In a one-time game, there is no opportunity to punish cheaters. In repeated games, cheaters can be punished.
Cooperation in one-time games is unstable.

51. Deciding to Cooperate Cooperate Cheat
When present value of costs of cheating exceeds present value of benefits of cheating
Achieved in an oligopoly market when all firms decide not to cheat
Cheat
When present value of benefits of cheating exceeds present value of costs of cheating

52. Retaliation for Cheating
Legal sanctions or fines levied against cheaters are illegal in most countries.
Cheaters are usually “punished” when rival firms push the game back to non-cooperative (Nash) equilibrium.

53. Deciding to Cooperate Where Bi = πCheat – πCooperate for i = 1,…, N
Where Cj = πCooperate – πNash for j = 1,…, P

54. A Firm’s Benefits & Costs of Cheating (Figure 13.5)

55. Trigger Strategies A rival’s cheating “triggers” punishment phase
Tit-for-tat strategy
Punishes after an episode of cheating & returns to cooperation if cheating ends
Grim strategy
Punishment continues forever, even if cheaters return to cooperation

56. Facilitating Practices
Legal tactics designed to make cooperation more likely
Four tactics
Price matching
Sale-price guarantees
Public pricing
Price leadership

57. Price Matching
Firm publicly announces that it will match any lower prices by rivals
Usually in advertisements
Discourages noncooperative price-cutting
Eliminates benefit to other firms from cutting prices

58. Sale-Price Guarantees
Firm promises customers who buy an item today that they are entitled to receive any sale price the firm might offer in some stipulated future period
Primary purpose is to make it costly for firms to cut prices

59. Public Pricing
Public prices facilitate quick detection of noncooperative price cuts
Timely & authentic
Example: Shared computerized reservation systems in the airline industry.
Early detection
Reduces PV of benefits of cheating
Increases PV of costs of cheating
Reduces likelihood of noncooperative price cuts

60. Price Leadership
Price leader sets its price at a level it believes will maximize total industry profit
Rest of firms cooperate by setting same price
Does not require explicit agreement
Generally lawful means of facilitating cooperative pricing

61. Cartels Most extreme form of cooperative oligopoly
Explicit collusive agreement to drive up prices by restricting total market output
Illegal in U.S., Canada, Mexico, Germany, & European Union

62. Cartels
Pricing schemes usually strategically unstable & difficult to maintain
Strong incentive to cheat by lowering price
When undetected, price cuts occur along very elastic single-firm demand curve
Lure of much greater revenues for any one firm that cuts price
Cartel members secretly cut prices causing price to fall sharply along a much steeper demand curve

63. Intel’s Incentive to Cheat (Figure 13.6)
Along dIntel, Intel can increase its sales and its market share.
Along DIntel, Intel can increase its sales but not its market share.

64. Tacit Collusion
Far less extreme form of cooperation among oligopoly firms
Cooperation occurs without any explicit agreement or any other facilitating practices

65. Strategic Entry Deterrence
Established firm(s) makes strategic moves designed to discourage or prevent entry of new firm(s) into a market
Two types of strategic moves
Limit pricing
Capacity expansion

66. Limit Pricing
Established firm(s) commits to setting price below profit-maximizing level to prevent entry
Under certain circumstances, an oligopolist (or monopolist), may make a credible commitment to charge a lower price forever

67. The key is making a credible commitment to a “low” post-entry price
Star Coffee
The key is making a credible commitment to a “low” post-entry price
Manager of Star Coffee

68. Limit Pricing: Entry Deterred
P* is the π-maximizing price
PL is the maximum-entry forestalling price.

69. Limit Pricing: Entry Occurs
PN is the Nash price

70. Star’s Price
BRB
BRS
$3.50 N
$3.50
Burned Bean’s Price

71. Star Coffee
The problem is that, if I am unable to make a credible commitment to permanently low prices, the manager of the Burned Bean knows I have an incentive to shift to the Nash price post-entry. Thus entry will not be deterred.
Manager of Star Coffee

72. Capacity Expansion
Established firm(s) can make the threat of a price cut credible by irreversibly increasing plant capacity
When increasing capacity results in lower marginal costs of production, the established firm’s best response to entry of a new firm may be to increase its own level of production
Requires established firm to cut its price to sell extra output

73. Excess Capacity Barrier to Entry (Figure 13.9)