Title: Game Theory and Competitive Strategy
1Chapter 13
- Game Theory and Competitive Strategy
2Topics to be Discussed
- Gaming and Strategic Decisions
- Dominant Strategies
- The Nash Equilibrium Revisited
- Repeated Games
3Topics to be Discussed
- Sequential Games
- Threats, Commitments, and Credibility
- Entry Deterrence
- Bargaining Strategy
- Auctions
4Gaming and Strategic Decisions
- Game is any situation in which players (the
participants) make strategic decisions - Ex firms competing with each other by setting
prices, group of consumers bidding against each
other in an auction - Strategic decisions result in payoffs to the
players outcomes that generate rewards or
benefits
5Gaming and Strategic Decisions
- Game theory tries to determine optimal strategy
for each player - Strategy is a rule or plan of action for playing
the game - Optimal strategy for a player is one that
maximizes the expected payoff - We consider players who are rational they think
through their actions
6Gaming and Strategic Decisions
- If I believe that my competitors are rational
and act to maximize their own profits, how should
I take their behavior into account when making my
own profit-maximizing decisions?(Text, p. 474)
7Noncooperative vs. Cooperative Games
- Cooperative Game
- Players negotiate binding contracts that allow
them to plan joint strategies - Example Buyer and seller negotiating the price
of a good or service or a joint venture by two
firms (i.e., Microsoft and Apple) - Binding contracts are possible
8Noncooperative vs. Cooperative Games
- Noncooperative Game
- Negotiation and enforcement of binding contracts
between players is not possible - Example Two competing firms, assuming the
others behavior, independently determine pricing
and advertising strategy to gain market share - Binding contracts are not possible
9Noncooperative vs. Cooperative Games
- The strategy design is based on understanding
your opponents point of view, and (assuming your
opponent is rational) deducing how he or she is
likely to respond to your actions. (Text, p. 475)
10Gaming and Strategic Decisions
- An Example How to buy a dollar bill
- Auction a dollar bill
- Highest bidder receives the dollar in return for
the amount bid - Second highest bidder must pay the amount he or
she bid but gets nothing in return - How much would you bid for a dollar?
- Typically bid more for the dollar when faced with
loss as second highest bidder
11Acquiring a Company
- Scenario
- Company A The Acquirer
- Company T The Target
- A will offer cash for all of Ts shares
- The value and viability of T depends on the
outcome of a current oil exploration project
12Acquiring a Company
- Project failure Ts value 0
- Project success Ts value 100/share
- All outcomes in between equally likely
- Ts value will be 50 greater with As management
13Acquiring a Company
- Scenario
- A must submit the proposal before the exploration
outcome is known - T will not choose to accept or reject until after
the outcome is known only to T - Company T will accept any offer that is greater
than the per share value of the company under
current management - How much should A offer?
14Dominant Strategies
- Dominant Strategy is one that is optimal no
matter what an opponent does - An Example
- A and B sell competing products
- They are deciding whether to undertake
advertising campaigns
15Payoff Matrix for Advertising Game
Firm B
Dont Advertise
Advertise
Advertise
Firm A
Dont Advertise
16Payoff Matrix for Advertising Game
- Observations
- A regardless of B, advertising is the best
- B regardless of A, advertising is best
17Payoff Matrix for Advertising Game
- Observations
- Dominant strategy for A and B is to advertise
- Do not worry about the other player
- Equilibrium in dominant strategy
18Dominant Strategies
- Equilibrium in dominant strategies
- Outcome of a game in which each firm is doing the
best it can regardless of what its competitors
are doing - Optimal strategy is determined without worrying
about the actions of other players - However, not every game has a dominant strategy
for each player
19Dominant Strategies
- Game Without Dominant Strategy
- The optimal decision of a player without a
dominant strategy will depend on what the other
player does - Revising the payoff matrix, we can see a
situation where no dominant strategy exists
20Modified Advertising Game
Firm B
Dont Advertise
Advertise
Advertise
Firm A
Dont Advertise
21Modified Advertising Game
- Observations
- A No dominant strategy depends on Bs actions
- B Dominant strategy is to advertise
- Firm A determines Bs dominant strategy and makes
its decision accordingly
22The Nash Equilibrium Revisited
- A dominant strategy is stable, but in many games
one or more party does not have a dominant
strategy - A more general equilibrium concept is the Nash
Equilibrium introduced in Chapter 12 - A set of strategies (or actions) such that each
player is doing the best it can given the actions
of its opponents
23The Nash Equilibrium Revisited
- None of the players have incentive to deviate
from its Nash strategy, therefore it is stable - In the Cournot model, each firm sets its own
price assuming the other firms outputs are
fixed. Cournot equilibrium is a Nash Equilibrium.
24The Nash Equilibrium Revisited
- Dominant Strategy
- Im doing the best I can no matter what you do.
Youre doing the best you can no matter what I
do. - Nash Equilibrium
- Im doing the best I can given what you are
doing. Youre doing the best you can given what I
am doing. - Dominant strategy is a special case of Nash
equilibrium
25The Nash Equilibrium Revisited
- Two cereal companies face a market in which two
new types of cereal can be successfully
introduced, provided each type is introduced by
only one firm - Product Choice Problem
- Market for one producer of crispy cereal
- Market for one producer of sweet cereal
- Each firm only has the resources to introduce one
cereal - Noncooperative
26Product Choice Problem
Firm 2
Crispy
Sweet
Crispy
Firm 1
Sweet
27Product Choice Problem
- If Firm 1 hears Firm 2 is introducing a new sweet
cereal, its best action is to make crispy - Bottom left corner is Nash equilibrium
- What is other Nash Equilibrium?
28Beach Location Game
- Scenario
- Two competitors, Y and C, selling soft drinks
- Beach is 200 yards long
- Sunbathers are spread evenly along the beach
- Price Y Price C
- Customer will buy from the closest vendor
29Beach Location Game
- Where will the competitors locate (i.e., where is
the Nash equilibrium)? - Will want to all locate in center of beach
- Similar to groups of gas stations, car
dealerships, etc.
30The Nash Equilibrium Revisited
- Maximin Strategies - Scenario
- Two firms compete selling file encryption
software - They both use the same encryption standard (files
encrypted by one software can be read by the
other - advantage to consumers) - Firm 1 has a much larger market share than Firm 2
- Both are considering investing in a new
encryption standard
31Maximin Strategy
Firm 2
Dont invest
Invest
Dont invest
Firm 1
Invest
32Maximin Strategy
- Observations
- Dominant strategy Firm 2 Invest
- Firm 1 should expect Firm 2 to invest
- Nash equilibrium
- Firm 1 invest
- Firm 2 Invest
- This assumes Firm 2 understands the game and is
rational
33Maximin Strategy
- Observations
- If Firm 2 does not invest, Firm 1 incurs
significant losses - Firm 1 might play dont invest
- Minimize losses to 10 maximin strategy
34Maximin Strategy
- If both are rational and informed
- Both firms invest
- Nash equilibrium
- If Player 2 is not rational or completely
informed - Firm 1s maximin strategy is to not invest
- Firm 2s maximin strategy is to invest
- If 1 knows 2 is using a maximin strategy, 1 would
invest
35Maximin Strategy
- If Firm 1 is unsure about what Firm 2 will do, it
can assign probabilities to each possible action - Could use a strategy that maximizes its expected
payoff - Firm 1s strategy depends critically on its
assessment of probabilities for Firm 2
36Prisoners Dilemma
Prisoner B
Confess
Dont Confess
Confess
Prisoner A
Dont Confess
37Prisoners Dilemma
- What is the
- Dominant strategy
- Nash equilibrium
- Maximin solution
- Dominant strategies are also maximin strategies
- Both confess is both Nash equilibrium and maximin
solution
38Mixed Strategy
- Pure Strategy
- Player makes a specific choice or takes a
specific action - Mixed Strategy
- Player makes a random choice among two or more
possible actions, based on a set of chosen
probabilities
39Matching Pennies
Player B
Heads
Tails
Heads
Player A
Tails
40Matching Pennies
- Pure strategy No Nash equilibrium
- No combination of head and tails leaves both
players better off - Mixed strategy Random choice is a Nash
equilibrium
41Matching Pennies
- Player A might flip coin playing heads with ½
probability and tails with ½ probability - If both players follow this strategy, there is a
Nash equilibrium both players will be doing the
best they can given what their opponent is doing - Although the outcome is random, the expected
payoff is 0 for each player
42Mixed Strategy
- One reason to consider mixed strategies is when
there is a game that does not have any Nash
equilibriums in pure strategy - When allowing for mixed strategies, every game
has a Nash equilibrium - Mixed strategies are popular for games like poker
- A firm might not find it reasonable
43The Battle of the Sexes
Joan
Wrestling
Opera
Wrestling
Jim
Opera
44The Battle of the Sexes
- Pure Strategy
- Both watch wrestling
- Both watch opera
- Mixed Strategy
- Jim chooses wrestling
- Joan chooses wrestling
45Repeated Games
- Game in which actions are taken and payoffs are
received over and over again - Oligopolistic firms play a repeated game
- With each repetition of the Prisoners Dilemma,
firms can develop reputations about their
behavior and study the behavior of their
competitors
46Pricing Problem
Firm 2
Low Price
High Price
Low Price
Firm 1
High Price
47Pricing Problem
- How does a firm find a strategy that would work
best on average against all or almost all other
strategies? - Tit-for-tat strategy
- Repeated game strategy in which a player responds
in kind to an opponents previous play,
cooperating with cooperative opponents and
retaliating against uncooperative ones
48Tit-for-Tat Strategy
- What if the game is infinitely repeated?
- Competitors repeatedly set price every month,
forever - Tit-for-tat strategy is rational
- If competitor charges low price and undercuts
firm - Will get high profits that month but know I will
lower price next month - Both of us will get lower profits if keep
undercutting, so not rational to undercut
49Tit-for-Tat Strategy
- What if repeated a finite number of times?
- If both firms are rational, they will charge high
prices until the last month - After the last month, there is no retaliation
possible - But in the month before last month, knowing that
will charge low price in last month, will charge
low price in month before - Keep going and see that only rational outcome is
for both firms to charge low price every month
50Tit-for-Tat Strategy
- If firms dont believe their competitors are
rational or think perhaps they arent,
cooperative behavior is a good strategy - Most managers dont know how long they will be
competing with their rivals - In a repeated game, prisoners dilemma can have
cooperative outcome
51Repeated Games
- Conclusion
- Cooperation is difficult at best since these
factors may change in the long run - Need a small number of firms
- Need stable demand and cost conditions
- This could lead to price wars if dont have them
52Oligopolistic Cooperationin the Water Meter
Industry
- Characteristics of the Market
- Four producers of water meters
- Rockwell International
- Badger Meter
- Neptune Water Meter Company
- Hersey Products
- Rockwell has about 35 of market share
- Badger, Neptune, and Hersey combined have about a
50 to 55 share
53Oligopolistic Cooperationin the Water Meter
Industry
- Most buyers are municipal water utilities
- Very inelastic demand
- Not a significant part of the budget for
providing water - Demand is stable
- Demand grows steadily with population
- Utilities have long-standing relationships with
suppliers - Reluctant to switch
54Oligopolistic Cooperationin the Water Meter
Industry
- Significant economies of scale
- Both long term relationship and economies of
scale represent barriers to entry - Hard for new firms to enter market
- If firms were to cooperate, could earn
significant monopoly profits - If compete aggressively to gain market share,
profits will fall to competitive levels
55Oligopolistic Cooperationin the Water Meter
Industry
- This is a Prisoners Dilemma what should the
firms do? - Lower price to a competitive level
- Cooperate
- Companies have been playing repeated game for
decades - Cooperation has prevailed given market
characteristics
56Sequential Games
- Players move in turn, responding to each others
actions and reactions - Ex Stackelberg model (ch. 12)
- Responding to a competitors ad campaign
- Entry decisions
- Responding to regulatory policy
57Sequential Games
- Going back to the product choice problem
- Two new (sweet, crispy) cereals
- Successful only if each firm produces one cereal
- Sweet will sell better
- Both still profitable with only one producer
58Modified Product Choice Problem
- If firms both announce their decisions
independently and simultaneously, they will both
pick sweet cereal and both will lose money - What if Firm 1 sped up production and introduced
new cereal first? - Now there is a sequential game
- Firm 1 will think about what Firm 2 will do
59Modified Product Choice Problem
Firm 2
Crispy
Sweet
Crispy
Firm 1
Sweet
60Extensive Form of a Game
- Extensive Form of a Game
- Representation of possible moves in a game in the
form of a decision tree - Allows one to work backward from the best outcome
for Firm 1
61Product Choice Game in Extensive Form
62Sequential Games
- The Advantage of Moving First
- In this product-choice game, there is a clear
advantage to moving first - The first firm can choose a large level of
output, thereby forcing second firm to choose a
small level - Can show the firms mover advantage by revising
the Stackelberg model and comparing to Cournot
63First Mover Advantage
64First Mover Advantage
65Choosing Output
Firm 2
7.5
10
15
7.5
10
Firm 1
15
66Choosing Output
- This payoff matrix illustrates various outcomes
- Move together, both produce 10
- If Firm 1 moves first (Q15), best Firm 2 can do
is 7.5
67Threats, Commitments, and Credibility
- Strategic Moves
- What actions can a firm take to gain advantage in
the marketplace? - Deter entry
- Induce competitors to reduce output, leave, raise
price - Implicit agreements that benefit one firm
68Threats, Commitments, and Credibility
- Strategic Move
- Action that gives a player an advantage by
constraining his behavior - Firm 1 must constrain his behavior to the extent
Firm 2 is convinced that he is committed
69Threats, Commitments, and Credibility
- How to Make the First Move
- Demonstrate Commitment
- Firm 1 must do more than announce they will
produce sweet cereal - Invest in expensive advertising campaign
- Buy large order of sugar and send invoice to Firm
2 - Commitment must be enough to induce Firm 2 to
make the decision Firm 1 wants it to make
70Threats, Commitments, and Credibility
- Empty Threats
- If a firm will be worse off if it charges a low
price, the threat of a low price is not credible
in the eyes of the competitors - When firms know the payoffs of each others
actions, firms cannot make threats the other firm
knows they will not follow - In our example, Firm 1 will always charge high
price and Firm 2 knows it
71Pricing of Computers and Word Processors
Firm 2
High Price
Low Price
High Price
Firm 1
Low Price
72Threats, Commitments, and Credibility
- Sometimes firms can make credible threats
- Scenario
- Race Car Motors, Inc. (RCM) produces cars
- Far Out Engines (FOE) produces specialty car
engines and sells most of them to RCM - Sequential game with RCM as the leader
- FOE has no power to threaten to build big engines
since RCM controls output
73Production Choice Problem
Race Car Motors
Small cars
Big cars
Small engines
Far Out Engines
Big engines
74Threats, Commitments, and Credibility
- RCM does best by producing small cars
- Knows that Far Out will then produce small
engines - Far Out prefers to make big engines
- Can Far Out induce Race Car to produce big cars
instead?
75Threats, Commitments, and Credibility
- Suppose Far Out threatens to produce big engines
no matter what RCM does? - Not credible since once RCM announces they are
producing small cars, FOE will not have incentive
to carry out threat - Can make threat credible by altering pay off
matrix by constraining its own choices - Shutting down or destroying some small engine
production capacity
76Modified Production Choice Problem
Race Car Motors
Small cars
Big cars
Small engines
Far Out Engines
Big engines
77Modified Production Choice Problem
- Strategic commitments can be effective but not
without risk - Rely heavily on accurate knowledge of payoff
matrix and industry - May have competitors out there that they dont
know about and lose sales
78Role of Reputation
- If Far Out gets the reputation of being
irrational - They threaten to produce large engines no matter
what Race Car does - Threat might be credible because irrational
people dont always make profit maximizing
decisions - A party thought to be crazy can lead to a
significant advantage
79Bargaining Strategy
- Bargaining situation can depend on ability to
affect relative bargaining position - Consider two firms introducing one of two
complementary goods - Firm 1 has cost advantage in Good A
- Firm 2 has cost advantage in Good B
80Bargaining Strategy
Firm 2
Produce A
Produce B
Produce A
Firm 1
Produce B
81Bargaining Strategy
- With collusion
- Firm 1 Produces A and Firm 2 produces B (50,50)
- Without collusion
- Firm 1 produces A and Firm 2 produces B (50,50)
- Nash equilibrium
82Bargaining Strategy
- Suppose each firm is also bargaining on the
decision to join in a research consortium with a
third firm - Dominant strategy is for both firms to enter
consortium
83Bargaining Strategy
Firm 2
Work alone
Enter consortium
Work alone
Firm 1
Enter consortium
84Bargaining Strategy
- Linking the Bargaining Problem
- Firm 1 announces it will join the consortium only
if Firm 2 agrees to produce A and Firm 1 will
produce B - Firm 2s best interest is to produce A with Firm
1 producing B - Firm 1s profit increases from 50 to 60
85Bargaining Strategy
- Strategic moves can be used in bargaining
- Combining issues in bargaining can benefit one
side at others expense
86Wal-Mart Stores Preemptive Investment Strategy
- How did Wal-Mart become the largest retailer in
the U.S. when many established retail chains were
closing their doors? - Gained monopoly power by opening in small towns
with no threat of other discount competition - Preemptive game with Nash equilibrium
87The Discount Store Preemption Game
Company X
Enter
Dont enter
Enter
Wal-Mart
Dont enter
88The Discount Store Preemption Game
- Two Nash equilibrium
- Low left
- Upper right
- Must be preemptive to win
89Entry Deterrence
- Barriers to entry important for monopoly power
- Economies of scale, patents and licenses, access
to critical inputs - Firms can also deter entry
- To deter entry, the incumbent firm must convince
any potential competitor that entry will be
unprofitable
90Entry Possibilities
Potential Entrant (X) (80 fixed costs)
Enter
Stay out
High price (accommodation)
Incumbent (I)
Low Price (warfare)
91Entry Deterrence
- Scenario
- If X does not enter, I makes a profit of 200
million - If X enters and charges a high price, I earns a
profit of 100 million and X earns 20 million - If X enters and charges a low price, I earns a
profit of 70 million and X earns -10 million
92Entry Deterrence
- Could threaten X with warfare if enters market
- Not credible because once X has entered, it is in
your best interest to accommodate and maintain
high price
93Entry Deterrence
- What if firm I makes an investment before entry
to increase capacity? - Irrevocable commitment
- Gives new payoff matrix since profits will be
reduced by investment - Threat is completely credible
- Rational for Firm X to stay out of market
94Entry Deterrence
Potential Entrant (X)
Enter
Stay out
High price (accommodation)
Incumbent (I)
Low price (warfare)
95Entry Deterrence
- If incumbent has reputation of price cutting
competitors even at loss, then threat will be
credible - Short run losses may be offset by long run gains
as monopolist
96Entry Deterrence
- Production of commercial airlines exhibit
significant economies of scale - Airbus and Boeing considering new aircraft
- Suppose it is not economical for both firms to
produce the new aircraft
97Development of a New Aircraft
Airbus
Produce
Dont produce
Produce
Boeing
Dont produce
98Development of a New Aircraft
- Boeing has head start
- Boeing will produce
- Airbus will not produce
99Development of a New Aircraft
- Governments can change outcome of game
- European government agrees to subsidize Airbus
before Boeing decides to produce - With Airbus being subsidized, the payoff matrix
for the two firms would differ significantly
100Development of an AircraftAfter European Subsidy
Airbus
Produce
Dont produce
Produce
Boeing
Dont produce
101Development of an AircraftAfter European Subsidy
- Airbus will produce
- Boeing will not produce
Airbus
Produce
Dont produce
Produce
Boeing
Dont produce
102Diaper Wars
- Even though there are only two major firms,
competition is intense - The competition occurs mostly in the form of
cost-reducing innovation - Small cost savings can lead to capturing of
market share - Both firms spend significantly on RD
103Competing Through R D
Kimberly-Clark
RD
No RD
RD
PG
No RD
104Competing Through R D
- Both spend on RD
- Dominant strategy
- Why not cooperate?
- Strengthening Bargaining Power
- Credibility
- Reducing flexibility
105Auctions
- Markets in which products are bought and sold
through formal bidding processes - Encourages competition that increases sellers
revenue - Low cost of transactions
- Useful for unique items or those with fluctuating
value - Tokyo fish market
106Auction Formats
- Traditional English (oral)
- Seller actively solicits progressively higher
bids from a group of potential buyers - Buyers are always aware of highest bid
- Stops when no one passes highest bid
107Auction Formats
- Dutch auction
- Seller begins by offering item at relatively high
price, then reduces it by fixed amounts until
item is sold - First buyer accepting offered price can buy item
at that price
108Auction Formats
- Sealed-bid
- All bids are made simultaneously in sealed
envelopes, where winning bid is the one who
submitted highest bid - First price
- Sales price equals highest bid
- Second price
- Sales price equals second highest bid
109Valuation and Information
- How to choose an auction format
- Private-value auction bidder knows individual
valuations of object, but valuations differ from
bidder to bidder - Signed baseball
- Common-value auction bidders uncertain what the
value is - Offshore oil reserve
110Price-Value Auctions
- Each bidder must choose bidding strategy
- Payoff for winning is reservation price minus
price paid - Payoff for losing is zero
111Private Value Auction
- English oral auction and secondprice sealed bid
auctions - Bidding truthfully is dominant strategy
- Pay based on value of second highest bidder so no
incentive not to bid reservation price - Risk to bidding higher than reservation price
112Private Value Auctions
- English auction
- Continue bidding until second person is unwilling
to make bid - Sealed-bid auction
- Winning bid approximately equal to the second
highest bidders reservation price - Both yield the same revenue
113Common Value Auctions
- Winners Curse
- The winner is worse off because they
overestimated the value of the item and thereby
overbid - Must reduce bid by amount equal to the expected
error of the winning bidder - If a lot of variation in other bidders, then
estimates are fairly imprecise
114Maximizing Auction Revenue
- Private Value Auction
- Encourages many bidders to increase expected bid
of winner - Common Value Auction
- Uses open rather than sealed bid
- Generates greater revenue
- Reveals information about true value, reducing
concern of winners curse
115Maximizing Auction Revenue
- Private value auction
- Sets min bid equal to or higher than value to you
of keeping good for future sale - Protects against loss if bidders are unaware of
value - Increases size of bids by letting bidders think
item is valuable - No sale could make bidders think item is low
quality
116Bidding and Collusion
- Buyers can allow benefit from collusion
- Can be done legally through buying groups
- Can be done illegally through collusive
agreements that violate antitrust laws - Collusion is not easy because of large incentive
to cheat - Repeated auctions allow for penalizing
participants that break agreement
117Bidding and Collusion
- Examples
- Collusion among baseball owners to limit their
bidding for free agent players in the 1980s - Two of the worlds most successful auction houses
were found guilty of agreeing to fix prices of
commissions - Sothebys and Christies
118Internet Auctions
- Popularity of auctions has skyrocketed with
growth of internet - Most popular site is eBay
- Dominates online person-person auction industry
- Subject to large network externalities
- Choose auction site with largest number of
potential bidders
119Internet Auctions
- eBay auctions are somewhat different from types
discussed - A few caveats
- No quality control function
- Poor seller feedback
- Bid manipulation may occur