| 摘要: | 本研究探討在成本不對稱性, 產品差異化，和不完全信息下環保企業和污染企業併購的誘因。監理機構在不完全掌握污染程度和社會成本信息的前提下，透過釐定污染企業的排放稅項和綠能企業的產出補貼，引導綠能企業和污染企業的并購重組和節能減排，達至消費者、生產者、和社會的三贏局面。本文首先鑒別在完全信息下的最佳政策，然後比較不完全信息下的最優政策對社會福利的影響。設若監理機構高估排放程度，面對過高排放稅的污染企業有誘因併購環保企業，透過產能重組來降低稅負。然而，設若監理機構低估排放程度，污染企業所繳交的排放稅不足以誘導其併購環保企業從而降低環境污染。這反映了差異化企業在併購重組的過程中對社會福利的影響，在於降低污染排放和促進產業競爭的利益在一定程度上相互抵消。分析顯示，過高的排放稅會衍生過度的併購，從而降低市場競爭程度而過於降低污染排放對社會大衆的影響。相類似地，過低的排放稅會降低企業併購的慾望，從而失去技術轉移而降低污染的可能。本文提倡，在監理機構缺乏精準的污染程度信息和污染程度分散的情況下，不作監管或許比監管更符合社會利益。 ;This research considers merger incentives of green and brown firms under cost asymmetry, product differentiation, and asymmetric information. We assume that the regulator has incomplete information on pollution intensity and associated social cost, and this article identifies the regulator's emission fees on the more polluting brown firms and production subsidies on the less polluting green firms, which provide incentives for differentiated firms to merge, reallocate output, and reduce pollution that is beneficial to consumers, producers, and the society as a whole. We first identify, as a benchmark, the regulator's optimal policy under complete information (the "first-best" policy), and compare it with the regulator's policy under incomplete information (the "second-best" policy), which forms a basis for the evaluation of social welfare under different information contexts. Specifically, when the regulator overestimates firms' pollution intensity, firms are subject to excessive emission fees that induce their mergers with and output shifts to the least polluting firm. However, when the regulator underestimates firms' pollution intensity, firms are subject to suboptimal emission fees that ameliorate their incentives to merge with less polluting rivals. This highlights the offsetting effects of mergers of differentiated firms on social welfare, which, on the one hand, increases market concentration, but on the other hand, reduces pollution. Our analysis show that environmental regulation may hinder welfare when excessive emission fees induce mergers that reduce market competition and completely offset the positive effects of pollution reduction on welfare. A similar argument applies when the regulator sets low emission fees and brown firms have no incentives to merge with and adopt the production technology of green firms to mitigate pollution. Accordingly, the results suggest that laissez-faire policy may be preferred to environmental regulation when the regulator has imprecise information on pollution intensity and the distribution of pollution intensity is volatile. |
