有關外部性計算的DWL - 經濟

補上原題目 中山大學碩士班98企管經濟學考題

suppose that your local internal provider,USA-line,

is congested around 8 pm on Thursday nights,which is

when many students downlaod Friday's homework assignment

from their professors' home pages.

Thursday nights represent the peak volume time for USA-line.

USA-line's supply curve can be represented as P=2+2Q.

The cost of the congestion during peak times can be represented as P=Q.

The marginal benefit during peak times can be represented as P=18-Q.

If USA-line is unware of the externality effects of the congest during

peak on-line tines,what is the value of the deadweight loss??


(A) 2.66

(B) 5.32

(C) 8

(D) 14.21




抱歉 不會BBS畫圖

概敘一下題目

需求函數: P=18-Q

私人成本: MPC=2+2Q

外部性成本: MDC=Q



社會總成本 MSC=MPC+MDC=2+2Q+Q=2+3Q


我有求出

私人均衡解: Q=16/3, P=38/3

社會福利最大的解: Q=4 ,P=14


問題來了

我不是很確定這邊DWL的面積是哪一塊


而且這邊福利的觀念有點搞混

希望有人可以點出我的盲點


感恩


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