#### Transcript Chap 12.1

```CHAPTER 12
CHAPTER 12
McGraw-Hill/Irwin
MONOPOLY
Chapter Outline
Defining Monopoly
Five Sources Of Monopoly
The Profit-maximizing Monopolist
A Monopolist Has No Supply Curve
Price Discrimination
The Efficiency Loss From Monopoly
Public Policy Toward Natural Monopoly
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What is a Monopoly?
Monopoly: a market structure in which a
single seller of a product with no close
substitutes serves the entire market.
A monopoly has significant control over the
price it charges.
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Five Sources Of Monopoly
1. Exclusive Control over Important
2.
3.
4.
5.
Inputs
Economies of Scale
Patents
Network Economies
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Figure 12.1: Natural Monopoly
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Natural Monopoly
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The Profit-maximizing Monopolist
The monopolist’s goal is to maximize
economic profit.
In the short run this means to choose the level
of output for which the difference between total
revenue and short-run total cost is greatest.
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Revenue for the Monopolist
As price falls, total revenue for the
monopolist does not rise linearly with
output.
Instead, it reaches a maximum value at the
quantity corresponding to the midpoint of the
demand curve after which it again begins to
fall.
Total revenue reaches its maximum value when
the price elasticity of demand is unity.
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Figure 12.2: The Total Revenue Curve
for a Perfect Competitor
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Figure 12.3: Demand, Total Revenue,
and Elasticity
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Figure 12.4: Total Cost, Revenue,
and Profit Curves for a Monopolist
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The Profit-maximizing Monopolist
Optimality condition for a monopolist: a
monopolist maximizes profit by choosing
the level of output where marginal revenue
equals marginal cost.
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Figure 12.5: Changes in Total Revenue
Resulting from a Price Cut
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Revenue Curves
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Figure 12.6: Marginal Revenue
and Position on the Demand Curve
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Marginal Revenue And Elasticity
The less elastic demand is with respect to
price, the more price will exceed marginal
revenue.
For all elasticity values less than 1 in absolute
value marginal revenue will be negative.
For all elasticity values larger than 1 in absolute
value marginal revenue will be positive.
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Figure 12.7: The Demand Curve and
Corresponding Marginal Revenue Curve
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Figure 12.8: A Specific Linear
Demand Curve and the Corresponding
Marginal Revenue Curve
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Figure 12.9: The Profit-Maximizing
Price and Quantity for a Monopolist
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Monopoly Production: Part I
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Monopoly Production: Part II
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