1. Externalities

2. Externalities Governments can sometimes improve market outcomes
Why do markets fail to allocate resources efficiently?
How can government policies improve market’s allocation?

3. Externalities Market failure occurs as a result of
Market power
Externalities
Externality is the uncompensated impact of one person’s action on the well-being of a bystander
Adverse impact on the bystander is called a negative externality
Beneficial impact on the bystander is called a positive externality

4. Externalities and Market Inefficiency
Externalities cause markets to be inefficient, and thus fail.
Demand curve reflects the value to the buyers and supply curve reflects the cost to the seller
At market equilibrium, total surplus is maximized
In the absence of externalities, market equilibrium is efficient
Both decision-makers fail to take account of the external effects of their behavior

5. Negative Externalities in Production
Negative externalities in production or consumption sometimes lead markets to produce a larger quantity than is socially desirable.
The Social Costs of production or consumption are greater than the private cost or private benefit by producers and consumers.
This leads to market failure.

6. Negative Externalities in Production
Due to the negative externality, social cost is greater than private cost
Social cost is the cost to the society of producing a product with a negative externality
The difference between social cost and private cost is the cost of the negative externality
The intersection between the demand curve and the social cost curve gives the optimum level of production

7. Negative Externalities in Production
In the presence of a negative externality:
Social cost> private cost
Optimum quantity < market equilibrium quantity
The reduction in production raises economic well-being
Economic well-being can be measured using the concept of deadweight loss
Deadweight loss is the fall in total surplus that results from a market distortion, such as tax or tariff.

8. Economic welfare
At market equilibrium, welfare is equal to the total surplus
Producer surplus is measured as amount received by the sellers- social cost to the society
At optimal quantity of production, consumer surplus is reduced but producer surplus increases
The dead weight loss of producing at market equilibrium level rather than at optimal level is equal to the area of the triangle formed by the social-cost curve and demand curve

9. Economic welfare
The dead weight loss is associated with the negative production externality
Pigovian taxes:
The government can internalize the externality by imposing a tax on the producer. The tax shifts private cost supply up to social cost supply and eliminates the deadweight loss.
Internalize an externality means to alter incentives so that people take account of the external effects of their actions
Pigovian taxes are enacted to correct the effects of the negative externalities

10. Positive Externalities in Production
Social cost of production = Private cost technology spillover
The optimal quantity is larger than the equilibrium market quantity
The positive externality can be internalized by imposing a Pigovian subsidy
Patents are an example of internalizing positive externalities

11. Externalities in Consumption
The analysis of consumption externalities is similar to that of production externalities
The demand curve does not reflect the value of the good from society’s point of view
Negative consumption externality (tax)
Positive consumption externality (subsidy)

12. Externalities : Conclusion
Negative externalities in production or consumption lead markets to produce a larger quantity than is socially desirable.
Positive externalities in production or consumption lead markets to produce a smaller quantity than is socially desirable.
Government can internalize externalities by
Levying a tax on goods with negative externalities
Imposing a subsidy on goods with positive externalities

13. Private Solutions to Externalities
Is it possible for private actors to allocate resources at the social optimum level?
Types of private solutions:
Moral codes and social sanctions
Charities
Self-interest of involved/relevant parties
Integration of different types of business
Contracts

14. Private Solutions to Externalities
The Coase theorem proposes that if private parties can bargain without cost over the allocation of resources, they can solve the problems of externalities on their own.
The Coase theorem says that whatever the initial distribution of rights, the interested parties can always reach a bargain in which everyone is better off and the outcome is efficient.

15. Private Solutions to Externalities
Why private solutions do not always work?
Transaction costs are costs that parties incur in the process of agreeing and following through on a bargain
Coordination costs increase as the number of interested parties increase
Government is an institution designed for collective action

16. Public Policies Toward Externalities
Regulation- dictating maximum level/ adopting a particular technology
Pigovian taxes and subsidies
Pigovian taxes and subsidies are more efficient than regulation as they achieve the same result by conferring a lower cost on the society
Tradable pollution permits- limits the supply of pollution permits and the demand curve sets the price for pollution
Pigovian Tax- sets a price on pollution and the demand curve determines the quantity of pollution

17. Should economics be used in the analysis of pollution?
Hint: People face tradeoffs and if clean environment is treated as a commodity ???