Chapter 18. Externalities and Public Goods. Externalities. Negative Externalities. Positive Externalities

Transcription

1 Chapter 18 Externalities and Public Goods Externalities Externalities are the effects of production and consumption activities not directly reflected in the market They can be negative or positive Chapter 18 1 Chapter 18 2 Negative Externalities Action by one party imposes a cost on another party Plant dumps waste in a river affecting those downstream The firm has not incentive to account for the external costs that it imposes on those downstream Positive Externalities Action by one party benefits another party Homeowner plants a beautiful garden where all the neighbors benefit from it Homeowner did not take their benefits into account when deciding to plant Chapter 18 3 Chapter 18 4

2 Negative Externalities and Scenario plant dumping waste Marginal External Cost (MEC) is the increase in cost imposed on fishermen downstream for each level of production. Marginal Social Cost (MSC) is MC plus MEC. Negative Externalities and Assume the firm has a fixed proportions production function and cannot alter its input combinations The only way to reduce waste is to reduce output of steel and quantity of steel initially produced is at the intersection of supply and demand Chapter 18 5 Chapter 18 6 Negative Externalities and External Costs The MC curve for the firm is the marginal costs of production Firm maximizes profit by producing where MC equals in a competitive firm As firm output increase, external cost on fishermen increases measured by the marginal external cost curve From a social point of view, the firm produces too much output P 1 MSC MC MEC P* P 1 There Firm is will profit MEC produce maximizing of production q1 at P1. firm from the produces waste released. at q1 while The the MSC is efficient true cost output of production. level is q*. MSC I S = MC I MEC I q* q 1 Firm output Q* Q 1 Industry output Chapter 18 7 Chapter 18 8

3 External Costs External Cost P* MSC I By no producing at the efficient level, there is a social cost on society S = MC I Aggregate social cost of negative externality encourage inefficient firms to remain in the industry and create excessive production in the long run. P 1 P 1 MEC I q* q 1 Firm output Q* Q 1 Industry output Chapter 18 9 Chapter Positive Externalities and External Benefits Externalities can also result in too little production, as can be shown in an example of home repair and landscaping. Repairs generate external benefits to the neighbors Show by the Marginal External Benefit curve (MEB) Marginal Social Benefit (MSB) curve adds MEB + Value P 1 P* When there are positive externalities (the benefits of repairs to neighbors), marginal social benefits MSB are higher than marginal benefits. A self-interested home owner invests q 1 in repairs. The efficient level of repairs q* is higher. The higher price P 1 discourages repair. Chapter q 1 q* Repair Level Chapter 18 12

4 Ways of Correcting Market Assumption: The market failure due to pollution Firm has chosen its profit-maximizing output level MSC is marginal social cost of emissions Ways of Correcting Market MCA is marginal cost of abating emissions Additional cost to firm of controlling pollution ownward sloping because when emissions are high, little cost to controlling them Chapter Chapter Ways of Correcting Market The Efficient Level of Emissions If the firm does not consider abatement, their profit maximizing level is 26 units of emissions Level where MCA is zero The socially efficient level of emissions is 12 where the MSC equals the MCA ollars/ unit of Emissions MSC At E o the marginal cost of abating emissions is greater than the marginal social cost. At E 1 the marginal social cost is greater than the marginal benefit. The efficient level of emissions is where MCA = MSC. Chapter MCA E 0 E* E Level of Emissions Chapter 18 16

5 Ways of Correcting Market Firms can be encouraged to reduce emissions to the efficient level in three ways Public Goods Characteristics For any given level of production the marginal cost of providing it to an additional consumer is zero. People cannot be excluded from consuming the good. Example use of lighthouse by a ship Chapter Chapter Public Goods goods Goods that people cannot be excluded from consuming, so that it is difficult or impossible to charge for their use Example: fireworks, national defense Efficiency and Pubic Goods Efficient level of private good is where marginal benefit equals marginal cost For a public good, the value of each person must be considered Can add demand of all those who value good Must equate the sum of these marginal benefits to the marginal cost of production Chapter Chapter 18 20

6 Efficient Public Good Provision Public Goods and Market Benefits (dollars) $7.00 $5.50 $4.00 $ is demand for consumer 1 2 is demand for consumer 2 is total demand for all consumers Efficient output occurs where MC = total MB 2 units of output. MB is $ $4.00 or $5.50. There is no way to provide some goods and services without benefiting everyone. Households do not have the incentive to pay what the item is worth to them. Free riders understate the value of a good or service so that they can enjoy its benefit without paying for it Output Chapter Chapter 18 22