1. Monopoly and Public Policy
Micro:
Econ: 26 62
Module
Monopoly and Public Policy
KRUGMAN'S
MICROECONOMICS for AP*
Margaret Ray and David Anderson

2. What you will learn in this Module:
The effects of monopoly on society’s welfare.
How policy-makers address the problems posed by monopoly.
The purpose of this module is to show that, when compared to perfect competition, the existence of monopoly reduces output and raises prices to consumers, while earning economic profit for the firm. By producing at an output below that where P=MC, monopoly causes a loss of total welfare: deadweight loss. In order to mitigate the negative consequences for consumers, government can adopt policies to regulate a monopoly firm.

3. The Welfare Effects of a Monopoly
The previous module showed that, when we compare monopoly to perfect competition:
Qm < Qc,
Pm > Pc, and
Monopoly profit is greater than zero.
This sounds bad for consumers and good for the firm. But is it bad for economic efficiency? We need to compare total welfare under perfect competition and compare it to total welfare under monopoly. We use the assumption that MC=ATC and is a horizontal line.
Perfect Competition:
The perfectly competitive output is Qc and the price is Pc=MC=ATC.
Total welfare is the sum of consumer and producer surplus. In this case, PS=0 so the entire surplus goes to the consumers. The area of this large triangle will be used as the benchmark so we can compare this triangle to the total surplus under monopoly.
The monopoly output is Qm and the price is Pm>MC=ATC.
Total welfare is still the sum of consumer and producer surplus. But we see that CS has shrunk while PS (profit) has increased. This PS is a transfer from consumers to the firm. However there is an area that used to belong to CS, but now belongs to nobody. This deadweight loss shows us that total surplus under monopoly is less than under perfect competition.
Total surplus under perfect competition is equal to: CSc
Total surplus under monopoly is equal to: CSm + PSm
Because of the deadweight loss, we can see that CSc > CSm + PSm
Economists see this loss of total welfare as a major drawback to monopoly and is an argument for regulation or prevention of monopolies.
What exactly is the deadweight loss?
It represents transactions (between Qc and Qm) that could have been made, but are not made under monopoly.
This will always occur when the level of output restricted such that Pm >MC.

4. Preventing Monopoly Power
Antitrust Laws address monopolization in markets
(Antitrust laws are discussed in more detail in the modules dealing with oligopoly)
Some monopolies arise due to mergers and acquisitions of rival companies or due to ownership of a critical production input. The government has Antitrust Laws to deal with the harmful effects of these types of monopolies.
But other monopolies are created by massive economies of scale. These natural monopolies exist when the average total cost of producing the entire market demand is lower if one firm exists, than they would be if several smaller firms existed.
If this is the case, it’s more efficient to allow the natural monopoly to exist, but with regulation to prevent abuse of pricing power and sizeable deadweight loss.

5. Dealing With A Natural Monopoly
Public ownership
Price regulation
Natural monopolies exist when the average total cost of producing the entire market demand is lower if one firm exists, than they would be if several smaller firms existed (e.g. economies of scale). If this is the case, it’s more efficient to allow the natural monopoly to exist, but with regulation to prevent deadweight loss.
The government can purchase and operate the firm. Because the government is not in the business of maximizing profit at Qm,Pm, prices should be lower for consumers. If the government could operate the market where Pc=MC, there would be no deadweight loss.
Downsides exist however. The government, as a very large bureaucracy with many other issues to deal with, is not always the best at keeping costs low. Waste and political favors may cause prices to rise and taxpayer money to be wasted.

6. Price Regulation Options for regulating a natural monopoly:
1. Regulated to the perfectly competitive outcome.
Output would be Qc and price Pc.
Consumer surplus would be maximized.
There would be no deadweight loss as Pc=MC.
The firm would suffer losses as Pc<ATC. Because society does not want to bankrupt the only electricity provider in the area, this regulation, while efficient would not be chosen.
2. Regulated such that the firm earns a normal profit.
Output would be Qr and price Pr.
Economic profit is zero as Pr=ATC.
Consumer surplus is larger than without regulation.
Some deadweight loss exists as Pr>MC, but not as much as would exist if the firm were unregulated.
Option 2 is a compromise between the unregulated monopoly outcome (worst for consumers and the most deadweight loss) and the perfectly competitive outcome (best for consumers, zero deadweight loss, but bankrupts the firm).