Topic 5:
Static Games
Cournot Competition
EC 3322
Semester I – 2008/2009
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
1
Introduction

A monopoly does not have to worry about how rivals will react to its action
simply because there are no rivals.

A competitive firm potentiall faces many rivals, but the firm and its rivals
are price takers  also no need to worry about rivals’ actions.

An oligopolist operating in a market with few competitors needs to
anticipate rivals’ actions/ strategies (e.g. prices, outputs, advertising, etc), as
these actions are going to affect its profit.

The oligopolist needs to choose an appropriate response to those actions
 similarly, rivals also need to anticipate the firm’s response and act
accordingly  interactive setting.

Game theory is an appropriate tool to analyze strategic actions in such an
interactive setting  important assumption: firms (or firms’ managers) are
rational decision makers.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
2
Introduction …

Consider the following story (taken from Dixit and Skeath (1999), Games of Strategy)



…”There were two friends taking Chemistry at Duke. Both had done pretty well on all of
the quizzes, the labs, and the midterm, so that going to the final they had a solid A. They
were so confident that the weekend before the final exam they decided to go to a party at
the University of Virginia. The party was so good that they overslept all day Sunday, and
got back too late to study for the Chemistry final that was scheduled for Monday morning.
Rather than take the final unprepared, they went to the professor with a sob story. They
said they had gone to the University of Virginia and had planned to come back in good
time to study for the final but had had a flat tire on the way back. Because they did not
have a spare, they had spent most of the night looking for help. Now they were too tired,
so could they please have a make-up final the next day?
The two studied all of Monday evening and came well prepared on Tuesday morning. The
professor placed them in separate rooms and handed the test to each. Each of them wrote
a good answer, and greatly relieved, but …
when they turned to the last page. It had just one question, worth 90 points. It was:
“Which tire?”….
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
3
Introduction …

Why are Professors So Mean   (taken from Dixit and Skeath (1999), Games
of Strategy)


Many professors have an inflexible rule not to accept late submission of
problem sets of term papers. Students think the professors must be really
hard heartened to behave this way.
However, the true strategic reason is often exactly the opposite. Most
professors are kindhearted , and would like to give their students every
reasonable break and accept any reasonable excuse. The trouble lies in
judging what is reasonable. It is hard to distinguish between similar excuses
and almost impossible to verify the truth. The professor knows that on each
occasion he will end up by giving the student the benefit of the doubt. But
the professor also knows that this is a slippery slope, As the students come
to know that the professor is a soft touch, they will procrastinate more and
produce even flimsier excuses. Deadline will cease to mean anything.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
4
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
5
Introduction …

Non-cooperative game theory vs. cooperative game theory. The former
refers to a setting in which each individual firm (a player) behave noncooperatively towards others (rivals players). The latter refers to a setting in
which a group of firms cooperate by forming a coalition.

We focus on non-cooperative game theory.

Different in timing of actions: simultaneous vs. sequential move games.

Different in the nature of information: complete vs. incomplete
information.

Oligopoly theory  no single unified theory, unlike theory of monopoly
and theory of perfect competition  theoretical predictions depend on the
game theoretical tools chosen.

Need a concept of equilibrium  to characterize the chosen optimal
strategies.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
6
Introduction …

A ‘game’ consists of:



A set of players (e.g. 2 firms (duopoly))
A set of feasible strategies (e.g. prices, quantities, etc) for all players
A set of payoffs (e.g. profits) for each player from all combinations of
strategies chosen by players.

Equilibrium concept  first formalized by John Nash  no player (firm)
wants to unilaterally change its chosen strategy given that no other player
(firm) change its strategy.

Equilibrium may not be ‘nice’  players (firms) can do better if they can
cooperate, but cooperation may be difficult to enforced (not credible) or
illegal.

Finding an equilibrium:  one way is by elimination of all (strictly)
dominated strategies, i.e. strategies that will never be chosen by players 
the elimination process should lead us to the dominant strategy.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
7
Introduction …

Ways of representing a Game:

Extensive Form Representation (Game Tree)

Normal Form Representation
In $ millions
Extensive Form
H
H
1,1
H
2
H
1
L
L
In $ millions
H’
0,2
2,0
2
L’
L
½, ½
sequential move
Yohanes E. Riyanto
2
1
L
1,1
H
0,2
2,0
2
L
½, ½
simultaneous move
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8
Introduction …

Definition: A strategy is a complete contingent plan (a full specification of
a player’s behavior at each of his/ her decision points) for a player in the
game.
Normal Form
In millions
H
H
L
H’
HH’
1,1
2,0
HL’
1,1
½ ,½
LH’
0,2
2,0
LL’
0,2
½,½
1,1
0,2
2,0
Player 2
2
L’
½, ½
extensive form - sequential move
Yohanes E. Riyanto
L
2
1
L
H
Player 1
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normal form - sequential move
9
Introduction …
In millions
H
H
L
L
H
0,2
2,0
2
L
1/2 , 1/2
2,0
0,2
1,1
Player 1
H
½, ½
extensive form - simultaneous move
Yohanes E. Riyanto
H
2
1
L
L
1,1
Player 2
EC 3322 (Industrial Organization I)
normal form - simultaneous move
10
Introduction …

When players can choose infinite number of actions, instead of only 2
actions  e.g. quantities, advertising expenditures, prices, etc.
1
a
exit
1-a,0
1-a,0
2
stay
in
Yohanes E. Riyanto
exit
1
2
sequential move
a
stay
in
a-a2, ¼ - a/2
a-a2, ¼ - a/2
simultaneous move
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11
Example …

Two airline companies, e.g. SIA and Qantas offering a daily flight from
Singapore to Sydney.

Assume that they already have set a price for the flight, but the departure
time is still undecided  the departure time is the strategy choice in this
game.

70% of consumers prefer evening departure while 30% prefer morning
departure.

If both airlines choose the same departure time, they share the market
share equally.

Payoffs to the airlines are determined by the market share obtained.

Both airlines choose the departure time simultaneously  we can represent
the payoffs in a matrix firm.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
12
Example …
What is the
equilibrium for this
The Pay-Off Matrix
game?
The left-hand
Qantas
number is the
pay-off to
Morning
Evening
SIA
Morning
(15, 15)
(30, 70)
(70, 30)
The right-hand
number is the
(35, 35)
pay-off
to
Qantas
SIA
Evening
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
13
Example
…
If Qantas
If Qantas
chooses an evening
chooses a morning
The Pay-Off Matrix
departure,
SIAdeparture,
The morning
departure SIA The morning departure
will also choose
willis choose
a dominated
is also a dominated
evening
evening
strategy for SIA
strategy for Qantas
Qantas
Both airlines
choose an
Morning
Evening
evening
departure
Morning
(15, 15)
(30, 70)
SIA
Evening
Yohanes E. Riyanto
(70, 30)
EC 3322 (Industrial Organization I)
(35, 35)
14
Example …

Suppose now that SIA has a frequent flyer program.

Thus, when both airlines choose the same departure times, SIA
will obtain 60% of market share.

This will change the payoff matrix.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
15
Example …
If SIA
The
Pay-Off Matrix
chooses
a morning
However, a
departure, Qantas
But
if SIAhas no
morning departure
Qantas
will choose
Qantas
chooses
an evening
is still a dominated
dominated
strategy
evening
departure,
Qantas
strategy for SIA
Qantas knows
willand
choose
this
so
Morning
Evening
morning
chooses
a morning
departure
Morning
(18, 12)
(30, 70)
SIA
Evening
Yohanes E. Riyanto
(70,
(70,30)
30)
EC 3322 (Industrial Organization I)
(42, 28)
16
Example …

What if there are no dominated strategies? We need to use the Nash
Equilibrium concept.

To show this  consider a modified version of our airlines game 
instead of choosing departure times, firms choose prices  For simplicity,
consider only two possible price levels.

Settings:


There are 60 consumers with a reservation price of $500 for the flight, and
another 120 consumers with the lower reservation price of $220.
Price discrimination is not possible (perhaps for regulatory reasons or because
the airlines don’t know the passenger types).

Costs are $200 per passenger no matter when the plane leaves.

airlines must choose between a price of $500 and a price of $220

If equal prices are charged the passengers are evenly shared. The low price
airline gets all passengers.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
17
Example
If SIA prices high
TheQantas
Pay-Offlow
Matrix
If both price high and
then both get 30 then Qantas gets
passengers.
If SIA prices
Profit
low
all 180 passengers. Qantas
per
andpassenger
Qantas high
isProfit
If both
low
perprice
passenger
then$300
SIA gets they each
get 90
is $20
PH = $500
PL = $220
all 180 passengers. passengers.
Profit per passenger
Profit per passenger
is $20
$20
P = $500 is($9000,$9000)
($0, $3600)
H
SIA
PL = $220
Yohanes E. Riyanto
($3600, $0)
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($1800, $1800)
18
Nash Equilibrium
(PH, PH) is a Nash
(PL, PL) is a Nash
There
is no simple
equilibrium.
The
Pay-Off
Matrix
There
are two(PNash
equilibrium.
,
P
)
cannot
be
H
L
way to choose
If both aretopricing
equilibria
thisa version
If between
both are pricing
Nash equilibrium.
and
familiarity
these equilibria
highCustom
thenofneither
wants
the
game
low then neither wants
If Qantas prices
Qantas
might
lead both
to
to“Regret”
change
to change
low
then SIA should
might
(PL, PHprice
) cannot
be
high also price low
both to
a Nashcause
equilibrium.
PH = $500
PL = $220
price
low
If Qantas
prices
high then SIA should
also pricePhigh
= $500 ($9000,
($9000,$9000)
($0, $3600)
$9000)
H
SIA
PL = $220
Yohanes E. Riyanto
($3600, $0)
EC 3322 (Industrial Organization I)
($1800, $1800)
19
Nash Equilibrium

Another very common game  prisoner’s dilemma game  illustrates that
the resulting NE outcome may be ‘inefficient’.
criminal 2
Confess

Don’t Confess
Confess
criminal 1
(6,6)
(1,10)
Don’t confess
(10,1)
(3,3)
So the only Nash equilibrium for this game is (C,C), even though (D,D)
gives both 1 and 2 better jail terms. The only Nash equilibrium is
inefficient.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
20
Nash Equilibrium

Consider the following price game between Firm A and Firm B
Firm B
H
Firm A

H
(100, 100)
L
(140, 25)
L
(25, 140)
(80, 80)
Had the firms been able to cooperate, they would have been able to obtain
higher payoffs.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
21
Mathematical Presentation of Nash Eq.

Suppose that there are 2 firms, 1 and 2  it can be generalized to n firms.

The profit of each firm is denoted by  i   i  si , s j  with i  1, 2, j  i.

Si , i  1, 2, is the set of all feasible strategies from which i can choose.
Thus, si and s j are the pair of strategies chosen by players i and j from
the set of feasible strategies.



Then, a pair of strategies si* , s*j is a Nash equilibrium if, for each firm i:
i  si* , s*j   i  si , s*j  for all si  S i , i  1,2, j  i.

Thus, for a strategy combination to be a Nash eq., the strategy si* must be
firm i’s best response to firm j’s strategy, sj* , and conversely sj* must be
firm j’s best response to strategy si*.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
22
Mathematical Presentation of Nash Eq.

Example:

 i is firm i’s profit and  si , s j  are firms i and j’s quantities (outputs). If the
profit function is continuous, concave and differentiable, we can solve for the
optimal strategy si* by solving the first-order condition for the max. problem:
 i  si , s j 
si

(1)
Similarly firm j will also choose its strategy optimally:
 j  si , s j 
s j

then solve for si*  s j 
0
0
then solve for s*j  si 
(2)
*
*
Finally the pair of Nash eq. outputs  si , s j  can be obtained by solving the
*
*
system of equation (1) and (2) simultaneously. To guarantee that  si , s j  are
the maximands we have to check for the second order condition for profit
maximization.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
23
Oligopoly Models



There are three dominant oligopoly models

Cournot

Bertrand

Stackelberg
They are distinguished by

the decision variable that firms choose

the timing of the underlying game
We will start first with Cournot Model.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
24
The Cournot Model

Consider the case of duopoly (2 competing firms) and there are no entry..

Firms produce homogenous (identical) product with the market demand
for the product:
P  A  BQ  A  B  q1  q2 
q1  quantity of firm 1
q2  quantity of firm 2

Marginal cost for each firm is constant at c per unit of output. Assume that
A>c.

To get the demand curve for one of the firms we treat the output of the
other firm as constant. So for firm 2, demand is
P   A  Bq1   Bq2

It can be depicted graphically as follows.
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EC 3322 (Industrial Organization I)
25
The Cournot Model
P = (A - Bq1) - Bq2
The profit-maximizing
choice of output by firm
2 depends upon the
output of firm 1
Marginal revenue for
Solve this
firm 2 is
TR2
MR2 =
= (A -for
Bq1)output
- 2Bq2
q2
q
MR2 = MC
A - Bq1 - 2Bq2 = c
Yohanes E. Riyanto
If the output of
firm 1 is increased
the demand curve
for firm 2 moves
to the left
$
A - Bq1
A - Bq’1
Demand
c
2
MC
MR2
q*2
Quantity
 q*2 = (A - c)/2B - q1/2
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26
The Cournot Model

We have
q*2 
 A  c  q1

2B
2
 this is the best response function for firm 2 (reaction function for
firm 2).

It gives firm 2’s profit-maximizing choice of output for any choice of
output by firm 1.

In a similar fashion, we can also derive the reaction function for firm 1.
q1* 

 A  c  q2

2B
2
Cournot-Nash equilibrium requires that both firms be on their
reaction functions.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
27
The Cournot Model
q2
(A-c)/B
(A-c)/2B
qC2
If firm 2 produces
The reaction function
The Cournot-Nash
(A-c)/B then firm
for firm 1 is
equilibrium is at
1 will choose to
q*1 = (A-c)/2B - q2/2
intersection
Firm 1’s reactionthe
function
produce no output
the reaction
Ifoffirm
2 produces
functions
nothing
then firmThe reaction function
for firm 2 is
1 will produce the
C
monopoly output q*2 = (A-c)/2B - q1/2
Firm
2’s reaction function
(A-c)/2B
qC1 (A-c)/2B
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(A-c)/B
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q1
28
The Cournot Model
q*1 = (A - c)/2B - q*2/2
q2
q*2 = (A - c)/2B - q*1/2
(A-c)/B
Firm 1’s reaction function
 3q*2/4 = (A - c)/4B
 q*2 = (A - c)/3B
(A-c)/2B
(A-c)/3B
 q*2 = (A - c)/2B - (A - c)/4B
+ q*2/4
C
Firm 2’s reaction function
(A-c)/2B
(A-c)/B
 q*1 = (A - c)/3B
q1
(A-c)/3B
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
29
The Cournot Model

In equilibrium each firm produces
q1*c  q2*c 

2 A  c
3B
Demand is P=A-BQ, thus price equals to
2 A  c
A  2c
*
P  A

3B
Total output is therefore
Q* 

 A  c
3

3
Profits of firms 1 and 2 are respectively
1*   *2   P*  c  q1*c   P*  c  q2*c
 A  c
1*   *2 
2
9B

A monopoly will produce
max 1M   P  c  q1   A  Bq1  c  q1
q
1
1M 
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 A  c
2

q1 
M
 A  c
2B
4B
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30
The Cournot Model

Competition between firms leads them to overproduce. The total output
produced is higher than in the monopoly case. The duopoly price is lower
than the monopoly price.
2 A  c
 A  c
 q1M 
3B
2B
A  2c
Ac
P* 
 P m  A  Bq1 
because A  c
3
2
It can be verified that, the duopoly output is still lower than the competitive
output  where P=MC.
Ac
P  MC  c c  A  2 BQ
Q
2B
MR
The overproduction is essentially due to the inability of firms to
credibly commit to cooperate  they are in a prisoner’s dilemma kind of
situation  more on this when we discuss collusion.
Q* 


Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
31
The Cournot Model (Many Firms)

Suppose there are N identical firms producing identical products.

Total output:
Q  q1  q2  q3  ...  qN
Demand is:


This denotes output
P  A  BQ  A  B  q1  q2  q3  ...  qN 
of every firm other
Consider firm 1, its demand can be expressed as:
than firm 1
P  A  BQ  A  B  q2  q3  ...  qN   Bq1

Use a simplifying notation:
Q1  q2  q3  ...  qN

So demand for firm 1 is:
P   A  BQ1   Bq1
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
32
The Cournot Model (Many Firms)
If the output of
the other firms
is increased
the demand curve
for firm 1 moves
to the left
$
P = (A - BQ-1) - Bq1
The profit-maximizing
choice of output by firm A - BQ-1
1 depends upon the
output of the other firms A - BQ’
-1
Marginal revenue for
Solve this
firm 1 is
for output
MR1 = (A - BQ-1) - 2Bq
q1 1
Demand
c
MC
MR1
q*1
MR1 = MC
Quantity
A - BQ-1 - 2Bq1 = c  q*1 = (A - c)/2B - Q-1/2
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
33
The Cournot Model (Many Firms)
q*1 = (A - c)/2B - Q-1/2
How do we solve this
As the
number
of
for
q*
?
1
The firms
are
identical.
As the
number
firms increases
output of
 q*1 = (A - c)/2B - (N - 1)q*1So
/2 in equilibrium they
firms
of each
firmincreases
falls
have identical
 (1 + (N - 1)/2)q*1 = (A - c)/2Bwillaggregate
output
As
the
number
ofof
outputs
As
increases
the
number
*
 q*1(N + 1)/2 = (A - c)/2B
Q increases
1  A  c  price
firms

2 profit
firms
increases

N
B
N

1


 q*1 = (A - c)/(N + 1)B
tends
marginal
cost
of to
each
firm falls
 A  Nc   c
 Q* = N(A - c)/(N + 1)B
lim
N   N  1
 P* = A - BQ* = (A + Nc)/(N + 1)
 Q*-1 = (N - 1)q*1
Profit of firm 1 is Π*1 = (P* - c)q*1 = (A - c)2/(N + 1)2B
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
34
Cournot-Nash Equilibrium: Different Costs

Marginal costs of firm 1 are c1 and of firm 2 are c2.

Demand is P = A - BQ = A - B(q1 + q2)



Solve this
We have marginal revenue for firm 1 as before. for output
q1
MR1 = (A - Bq2) - 2Bq1
A symmetric result
Equate to marginal cost: (A - Bqholds
c1
for
of
2) - 2Bq
1 = output
firm 2
 q*1 = (A - c1)/2B - q2/2
 q*2 = (A - c2)/2B - q1/2
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
35
Cournot-Nash Equilibrium: Different Costs
q2
(A-c1)/B
R1
q*1 = (A - c1)/2B - q*2/2
The equilibrium
If the marginal
output cost
of firm
2 q*
of firm
2 2 = (A - c2)/2B - q*1/2
What
happens
increases
and
of
falls
its reaction
 q*2 =to
(Athis
- c2)/2B - (A - c1)/4B
firmcurve
1 equilibrium
fallsshifts to when + q* /4
2
costs
change?
the
right
 3q*2/4 = (A - 2c2 + c1)/4B
 q*2 = (A - 2c2 + c1)/3B
(A-c2)/2B
R2
C
 q*1 = (A - 2c1 + c2)/3B
(A-c1)/2B
Yohanes E. Riyanto
(A-c2)/B
q1
EC 3322 (Industrial Organization I)
36
Cournot-Nash Equilibrium: Different Costs

In equilibrium the firms produce:
q1C 
 A  2c1  c2  and q C   A  2c2  c1 
2
3B
Q*  q1C  q2C 




 2 A  c1  c2 
3B
3B
The demand is P=A-BQ, thus the eq. price is:
 2 A  c1  c2  A  c1  c2
P*  A  

3
3


Profits are:
2
2
 A  2c1  c2 
 A  2c2  c1 
*
*
1 
and  2 
9B
9B
Equilibrium output is less than the competitive level.
Output is produced inefficiently  the low cost firm should produce all
the output.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
37
Concentration and Profitability

Consider the case of N firms with different marginal costs.

We can use the N-firms analysis with modification.

Recall that the demand for firm 1 is P   A  BQ1   Bq1


So then the demand for firm 1 is : P   A  BQi   Bqi , so the MR
can be derived as MR  A  BQ i  2 Bqi
But Q*-i + q*i = Q*
Equate MR=MC  and denote
and Athe- equilibrium
BQ* = P*solution by *.
A  BQ*i  2 Bq*i  ci

A  BQ*i  Bq*i  Bq*i  ci
A  B  Q*i  q*i   Bq*i  ci  0
P
P*  Bqi*  ci  0
P*  Bqi*  ci
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
38
Concentration and Profitability
P* - ci = Bq*i
The price-cost margin
Divide by P* and multiply the right-hand
for eachside
firmbyisQ*/Q*
determined by its
P* - ci
BQ* q*i
=
market share and
P*
P* Q*
demand elasticity
But BQ*/P* = 1/ and q*i/Q* = Average
si
price-cost
margin is
P c s
so: P* - ci = si

determined
by industry

P

P*
concentration
s P s c
Extending this we have
P c
 P c 


s 
P 
P
P

P* - c
H
=
s  H
P*

*
*
i
i
*
N
i 1
*
*
i
N
i 1
Yohanes E. Riyanto
i
*
* 2
i



N
i 1
*
i
N
*
i 1
*
*
i i

*
*

EC 3322 (Industrial Organization I)
39
Final Remarks

So far we consider only “pure” strategy equilibria  a player picks the
strategy with certainty (prob.=1), e.g. choosing ‘kick the ball to the
middle’ in a soccer penalty shootout..

“Mixed” strategies  the player uses a probabilistic mixture of the
available strategies, e.g. left, middle, right  thus randomize the strategies
 sometimes aims the left, middle or right.
Burger King
McDonalds
Yohanes E. Riyanto
Low
Price
Heavy
Advertising
Low
Price
(60, 35)
(56, 45)
Heavy
Advertising
(58, 50)
(60, 40)
EC 3322 (Industrial Organization I)
No Pure
Strategy Eq.
40
Final Remarks

Suppose Burger King believes that McDonald will play strategy L with
prob pM L and H with prob. pM H  1  pM L . When BK plays L, its
expected payoff is:
35 pM L  50 1  pM L 

If BK plays H, its expected payoff is:
45 pM L  40 1  pM L 

BK will be indifferent between L and H iff:
35 pM L  50 1  pM L   45 pM L  40 1  pM L 
50  15 pM L  40  5 pM L
pM L 

1
1
and 1  pM L  
2
2
Thus, when McDonald plays the optimal mixed strategy eq. with the
above prob. distribution then BK will be indifferent between playing L or
H.
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
41
Final Remarks

Similarly, when BK plays its optimal mixed strategy eq. then McDonald
will be indifferent between playing L or H.
60 pBL  56 1  pBL   58 pBL  60 1  pBL 
56  4 pBL  60  2 pBL
pBL 
2
1
and 1  pBL  
3
3
Burger King
pBL  2 / 3
Low
Price
pM L  1/ 2
1  p   1/ 3
Heavy
BL
Advertising
Low
Price
(60, 35)
(56, 45)
1  p   1/ 2 Heavy
Advertising
(58, 50)
(60, 40)
McDonalds
ML
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
42
Next … (Bertrand Price Competition)
Yohanes E. Riyanto
EC 3322 (Industrial Organization I)
43