86 Chapter Highlights
Externalities
A. Consumption externality occurs when an agent cares directly about another
agent’s consumption or production of some good
B. Production externality occurs when a firm’s production function depends on
choices of another firm or consumer
C. Example: smokers and nonsmokers
1. two roommates who consume smoke and money; one likes smoke, the other
doesn’t
2. depict preferences
3. depict endowment
a) each has $100
b) but what is initial endowment of smoke?
4. under some conditions, the amount of smoke is independent of the assign-
ment of property rights. Figure 31.2.
D. Production externalities
1. S, a steel firm and F, a fishery
2. steel: maxspss−cs(s, x)
E. Efficient solution
1. merge and maximize joint profits
2. internalize the externality
3.
max
5. joint firm takes interaction into account