| 摘要註: |
本文主要探討在上下游廠商連續獨佔及上游獨佔下游雙佔的架構下,廠商CSR行為關心生產過程中產生的汚染損失時,上下游廠商不同程度CSR行為下如何決定均衡時上游供應之單位價格及固定費用、下游產量、以及產業利潤,並再進行社會福利的分析。之後再延伸至考慮政府最適課稅干預時各種情況下之均衡及福利分析。結果顯示由於賽局結構的設定,上游廠商具先行者優勢,因此下游的CSR努力都會被上游所中性化。上游CSR程度增加將導致單位價格增加,但產量、固定費用及產業利潤減少,若下游雙佔時,僅單位價格及固定費用減少程度下降,其均衡大致不變。加入政府課稅後,上游廠商的CSR努力也因政府的先行者優勢而中性化,且單位稅額與上游的CSR存在替代關係。與未加入政府干預比較後發現其產量及固定費用不再受上游CSR所影響且產業利潤會隨之增加。由於政府介入前廠商關心的只有利潤及其CSR行為,因此政府介入後又擁有先行者優勢又關心整個社會福利,最終將導致社會福利提高。 In this paper we discuss the CSR behaviors of suppliers who care for pollution damage from production in a vertical industry structure of either successive monopoly or upstream monopoly and downstream duopoly, and investigate the equalibrium unit price, fixed cost, quantity, and industry profit. Then the model is extended to analyze the optimal tax intervention by the government and its effects on equilibrium, in the two scenarios, lastly, the social welfare is analyzed. The result reveals that since the game structure endows the upstream supplier with first-mover advantage, the CSR efforts of the downstream firm will be neutralized. The higher level of upstream CSR leads to higher unit price, lower quantities, fixed costs and industry profits. Downstream duopoly does not change qualitatively the equilibrium, but the effects of upstream CSR on the unit price and fixed costs are weakened. Considering optimal tax, the CSR efforts of the upstream firm will be neutralised by the government with the first-mover advantage, and unit tax will be a substitute to the upstream CSR. Compared with the laissez-faire scenario, we find that the upstream CSR no longer affects the quantities and fixed costs, and the industry profit is higher. As result of the first-mover advantage of government and its concern for the social welfare, social welfare is enhanced. |