Transcript Chapter 1
ECON 152 – PRINCIPLES OF MICROECONOMICS
Chapter 27: Oligopoly
and Strategic Behavior
Materials include content from Pearson Addison-Wesley which has been modified
by the instructor and displayed with permission of the publisher. All rights reserved.
Oligopoly
Oligopoly
A
market situation in which there
are very few sellers
Each seller knows that the other sellers will
react to its changes in prices and quantities
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Oligopoly
Characteristics of oligopoly
Small
number of firms
Interdependence
Strategic dependence
A situation in which one firm’s actions with respect to
price, quality, advertising, and related changes may
be strategically countered by the reactions of one or
more other firms in the industry
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Oligopoly
Why oligopoly occurs
Economies of scale
Barriers to entry
Mergers
Vertical Merger
The joining of a firm with another to which it sells an
output or from which it buys
an input
Horizontal Merger
The joining of firms that are producing or selling a similar
product
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Oligopoly
Determining the Existence of an Oligopoly
Concentration
Ratio
The percentage of all sales contributed by the
leading four or leading eight firms in an industry
It
is difficult to specify an arbitrary absolute
number to demonstrate the existence of an
oligopoly, but it is a good indicator.
Verification is usually based on the observed
strategies and behavior of the firms of the
industry.
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Computing the Four-Firm
Concentration Ratio
Firm
Annual Sales
($ Millions)
1
2
3
4
5 through 25
150
100
80
70
50
Total
450
Total number
of firms in
Industry = 25
400
= 88.9%
Four-firm concentration ratio =
450
Table 27-1
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E-Commerce Example:
Concentration in the Search-Engine Industry
Internet search-engines collect revenue
through advertisements posted on their
websites.
To measure the concentration ratio in this
industry, economists count the number of
searches conducted on each site.
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E-Commerce Example:
Concentration in the Search-Engine Industry
The four most frequently used searchengines are Google, Yahoo, AOL Time
Warner, and MSN.
The four-firm concentration ratio in this
industry is 91 percent, indicating that it
qualifies as an oligopoly.
8
Oligopoly, Inefficiency, and
Resource Allocation
Oligopolistic firms have some degree of market
power, which means each one can affect the
market price.
This creates some inefficiency in resource
allocation.
But to the extent that U.S. oligopolies must
compete with firms from other countries, their
market power is limited.
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Strategic Behavior
and Game Theory
Explaining the pricing and output behavior
of oligopoly markets
Reaction
Function
The manner in which one oligopolist reacts to a
change in price, output, or quality made by another
oligopolist in the industry
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Strategic Behavior
and Game Theory
Game Theory
A
way of describing the various possible
outcomes in any situation involving two
or more interacting individuals when those
individuals are aware of the interactive nature
of their situation and plan accordingly
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Strategic Behavior
and Game Theory
Cooperative Game
A
game in which the players explicitly
cooperate to make themselves better off
Noncooperative Game
A
game in which the players neither negotiate
nor cooperate in any way
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Strategic Behavior and Game Theory
Zero-Sum Game
A
game in which any gains within the group
are exactly offset by equal losses by the end
of the game
Negative-Sum Game
A
game in which players as a group lose at
the end of the game
Positive-Sum Game
A
game in which players as a group are better
off at the end of the game
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Strategic Behavior
and Game Theory
Strategies in noncooperative games
Strategy
Any rule that is used to make a choice
Any potential choice that can be made by players
in a game
Dominant
Strategies
Strategies that always yield the highest benefit
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Example: The Prisoner’s Dilemma
You and your partner rob a bank and get
caught.
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Prisoner’s Dilemma
You are separated and given these
options:
Both
confess and get five years in jail
Neither confess and get two years
One confess and the other does not
Confessor goes free
One who does not confess gets ten years
Assume you are Sam reacting to the possible
actions of Carol.
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The Prisoners’ Dilemma Payoff Matrix
Figure 27-1
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The Prisoners’ Dilemma Payoff Matrix
Confessing is better than not confessing.
Figure 27-1
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The Prisoners’ Dilemma Payoff Matrix
Confessing is better than not confessing.
Confessing is better than not confessing.
Figure 27-1
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Strategic Behavior and Game Theory
Applying game theory to pricing strategies
Would
you choose a high price or a low price?
Remember
No collusion
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Pricing Dilemma
The firms are separated and given these options:
Both charge high price and each gets $6 million
Both charge low price and each gets $4 million
One charges low price and the other high
Lower priced firm gets $8 million
Higher priced firm gets $2 million
Assume you are Firm #2 reacting to the possible
actions of Firm #1
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Strategic Behavior and Game Theory
Figure 27-2
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Strategic Behavior and Game Theory
Low is better than high.
Figure 27-2
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Strategic Behavior and Game Theory
Low is better than high.
Low is better than high.
Figure 27-2
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Strategic Behavior and Game Theory
Opportunistic Behavior
Actions
that ignore the possible long-run
benefits of cooperation and focus solely on
short-run gains
An example might be writing a check that you
know will bounce
Not realistic
Consequences tend to be more obvious
We make repeat transactions
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Strategic Behavior and Game Theory
Tit-for-Tat Strategic Behavior
In
game theory, cooperation that continues
so long as the other players continue to
cooperate
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Price Rigidity and the
Kinked Demand Curve
Price and Marginal Revenue per Unit
Panel (a)
d1
A
P0
d1
q0
Figure 27-3, Panel (a)
Quantity per Time Period
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Price Rigidity and the
Kinked Demand Curve
Panel (a)
Price and Marginal Revenue per Unit
d2
d1 is relatively elastic
• if one firm raises its
price the others will not
and it will lose market
share
d1
A
P0
d1
d2
q0
Figure 27-3, Panel (a)
Quantity per Time Period
d2 is relatively inelastic
• if one firm lowers its
price the others lower
their price so gain in sales
is small
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Price Rigidity and the
Kinked Demand Curve
Panel (a)
Price and Marginal Revenue per Unit
d2
d1 is relatively elastic
• if one firm raises its
price the others will not
and it will lose market
share
d1
A
P0
d1
MR 1
d2
q0
Figure 27-3, Panel (a)
Quantity per Time Period
d2 is relatively inelastic
• if one firm lowers its
price the others lower
their price so gain in sales
is small
29
Price Rigidity and the
Kinked Demand Curve
Panel (a)
Price and Marginal Revenue per Unit
d2
d1 is relatively elastic
• if one firm raises its
price the others will not
and it will lose market
share
d1
A
P0
d1
MR 1
MR2
d2
q0
Figure 27-3, Panel (a)
Quantity per Time Period
d2 is relatively inelastic
• if one firm lowers its
price the others lower
their price so gain in sales
is small
30
Price Rigidity and the
Kinked Demand Curve
Price and Marginal Revenue per Unit
Panel (b)
d1
P0
MR 1
The kinked demand curve
indicates the possibility
of price rigidity
A
d2
MR 2
q0
Figure 27-3, Panel (b)
Quantity per Time Period
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Price Rigidity and the
Kinked Demand Curve
Price, Marginal Revenue, and
Marginal Cost per Unit
d1
P0
MR1
MC '
MC
MC"
Changes in cost do
not impact output
and prices as long as
MC remains in the
vertical portion of MR
d2
MR2
q0
Quantity per Time Period
Figure 27-4
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Strategic Behavior with Implicit
Collusion: A Model of Price Leadership
Price Leadership
A
practice in many oligopolistic industries in
which the largest firm publishes its price list
ahead of its competitors, who then match
those announced prices
Price leadership behavior is apparent in the
overnight package delivery industry
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Strategic Behavior with Implicit
Collusion: A Model of Price Leadership
Price War
A
pricing campaign designed to drive
competing firms out of a market by repeatedly
cutting prices
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Strategic Behavior with Implicit
Collusion: A Model of Price Leadership
Markets where price wars are common
Cigarettes
Long-distance
telephone companies
Airlines
Diapers
Frozen
foods
PC hardware and software
35
Deterring Entry Into an Industry
Entry Deterrence Strategy - Any strategy undertaken
by firms in an industry, either individually or together,
with the intent or effect of raising the cost of entry into
the industry by a new firm
Increasing entry cost
Threat of price wars
Government regulations
Strategies – A group of colluding sellers
will set the highest common price without new firms
seeking to enter the industry
Raising switching costs for customers
Limit-Pricing
Non-compatible software
Non-transferability of college courses
36
Network Effects and Industry
Concentration
A network effect is a situation in which a
consumer’s inclination to use an item depends
on how many others use it.
In an industry selling products subject to network
effects, a small number of firms may be able to
secure the bulk of the payoffs resulting from
positive market feedback.
Oligopoly is likely to emerge as the prevailing
market structure.
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Comparing Market Structures
Market
Structure
Number
of
Sellers
Unrestricted
Entry and
Exit
Ability
to Set
Price
Long-Run
Economic
Profits
Possible
Product
Nonprice
Differentiation Competition Examples
Perfect
competition
Numerous
Yes
None
No
None
None
Agriculture,
roofing nails
Monopolistic
competition
Many
Yes
Some
No
Considerable
Yes
Toothpaste
toilet paper,
soap, retail
trade
Oligopoly
Few
Partial
Some
Yes
Frequent
Yes
Recorded
music, college
textbooks
Pure
monopoly
One
Not
for entry
Considerable
Yes
None
(product is
unique)
Yes
Some electric
companies,
some local
telephone
companies
Table 27-3
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ECON 152 – PRINCIPLES OF MICROECONOMICS
Chapter 27: Oligopoly
and Strategic Behavior
Materials include content from Pearson Addison-Wesley which has been modified
by the instructor and displayed with permission of the publisher. All rights reserved.