# Public Goods, Common Resources, and Externalities
## Different Types of Goods
- Public Goods: neither excludable nor rival, free market does a very BAD job.
- Private Goods: both excludable and rival, free market is very efficient in
distributing such goods.
- Club Goods: excludable but not rival, market does an OK job
- Common Resource: not excludable but rival, market does a very BAD job.
## Public Goods
- Free-rider problem
- Solutions
- Advertising
- Forcing everyone to pay
- Cost-benefit analysis can be sophisticated in some cases.
## Common Resources
- Tragedy of the Commons = if all the boats belong to one company, less boats
will be sent out... A single company controlling the whole industry will
consider the cost and benefits globally.
- Solutions
- Property rights and quotas.
- Tolls
## Externalities
- Externality (either positive or negative)
- An agent engages in an activity which changes the welfare of another agent
- The change in welfare goes uncompensated
- Problem is, the pollution cost is hard to measure, i.e. hard to internalize
the externalities
- Negative externality creates too much of a thing, positive externality creates
too little of a thing
- Private solution
- "Coase Theorem", as long as we can assign property rights, externalities can
be internalized by negotiation
- Sometimes transaction cost is too high to bring all agents together.
- Governmental solution
- Pollution quota
- Tax, in such case the quota can be traded among companies