External Cost ■ Scenario Marginal External Cost(MEC)is the cost imposed on fishermen downstream for each level of production o Marginal Social Cost (MSC)is MC plus MEC Chapter 18 Slide 6
Chapter 18 Slide 6 External Cost ◼ Scenario ⚫ Marginal External Cost (MEC) is the cost imposed on fishermen downstream for each level of production. ⚫ Marginal Social Cost (MSC) is MC plus MEC
External Costs When there are negative The differences is The profit maximizing firm externalities, the marginal the marginal external produces at q1 while the social cost MSC is higher cost MEC efficient output level is ql than the marginal cost Price MSC Price MC MSC S=MC The industry competitive output is Q1 while the efficient level is Q Aggregate social cost off negative externality MEC MEC D g 91 Firm output Q* Q1 Industry output
MC S = MCI D P1 Aggregate social cost of negative externality P1 q1 Q1 MSC MSCI When there are negative externalities, the marginal social cost MSC is higher than the marginal cost. External Costs Firm output Price Industry output Price MEC MECI The differences is the marginal external cost MEC. q* P* Q* The industry competitive output is Q1 while the efficient level is Q*. The profit maximizing firm produces at q1 while the efficient output level is q*
External Cost Negative Externalities encourage inefficient firms to remain in the industry and create excessive production in the long run Chapter 18 Slide 8
Chapter 18 Slide 8 External Cost ◼ Negative Externalities encourage inefficient firms to remain in the industry and create excessive production in the long run
Externalities a Positive EXternalities and Inefficiency Externalities can also result in too little production, as can be shown in an example of home repair and landscaping Chapter 18 Slide 9
Chapter 18 Slide 9 Externalities ◼ Positive Externalities and Inefficiency ⚫ Externalities can also result in too little production, as can be shown in an example of home repair and landscaping
External Benefits Value I MSB When there are positive externalities(the benefits of repairs to neighbors), marginal social benefits A self-interested home owner MSB are higher that invests q, in repairs. The marginal benefits D efficient level of repairs g* is higher. The higher price P discourages repair. P1 MC Is research and development MEB discouraged by positive externalities Repair Level Chapter 18 Slide 10
Chapter 18 Slide 10 P1 MC External Benefits Repair Level Value D Is research and development discouraged by positive externalities? q1 MSB MEB When there are positive externalities (the benefits of repairs to neighbors), marginal social benefits MSB are higher than marginal benefits D. q* P* A self-interested home owner invests q1 in repairs. The efficient level of repairs q* is higher. The higher price P1 discourages repair