環境企業社會責任於異質雙佔市場的經濟福利分析

Environmental Corporate Social Responsibilities in Differentiated Duopoly: A Welfare Analysis

在污染產業中，相對於數量競爭而言，文獻上價格競爭導致較高的市場總產出與社會福利的結論將不必然成立。本文檢視污染產業中，數量與價格競爭環境對於廠商策略性履行環境企業社會責任的誘因與經濟福利的影響。研究結果指出，相對於價格競爭模式下的市場均衡，廠商在數量競爭模式下產量較低，價格較高，減污投入較多，污染排放較少。換言之，在價格競爭模式下，較高的產量雖然提升了消費者剩餘，較少的減污投入卻增加了環境污染損害。因此，權衡消費者剩餘與環境污染損害對於社會福利消長的影響，我們發現當污染造成的邊際損害過大的情況下，數量競爭模式下的社會福利將會高於價格競爭模式下的社會福利。

The well-known result that price rather than quantity competitiondelivers a higher amount of output and consequently higher social welfaremay not hold in a polluting industry. This paper examines firms’ incentivesfor undertaking strategic ECSR activities under quantity and pricecompetition, respectively. Compared to the equilibrium outcome underprice competition, we find that the firms produce fewer outputs, chargehigher prices, invest more in ECSR activities, and discharge less emissionunder quantity competition. In other words, while a higher output levelincreases consumer surplus, a lower level of ECSR investment intensifiesenvironmental damage. Due to the trade-off between consumer surplusand environmental damage, social welfare is higher under quantitycompetition if the marginal environmental damage is too large.