生產效率、非歧視性稅制與市場結構

Production Efficiencies, Unprejudiced Taxes and Market Structure

The goal of this paper is to show that the market structure for an industry which features cost efficiencies differences may be determined by either lump-sum tax or excise tax. We found that competition between firms may not be able to lead to production efficiency for the industry. When an excise tax is imposed and the increased cost may lead a pre-tax duopoly market into a monopoly market that is operated by the efficient firm. However, instead of excise tax, when a lump-sum tax is considered, for some particular amount of tax, the less efficient one may monopolize the market. It is possible that a distortional tax (excise tax) generate higher social surplus than that under lump-sum tax, a non-distortional tax. 本文旨在探討非歧視性稅制對異質廠商競爭行為的影響。在非歧視性稅制下市場競爭並不能保證生產效率：在某些特定的稅額下，較不具效率的獨占廠商將寧可付出相對高額的定額稅也不願意政府減稅。獨占租對潛在具有效率廠商形成更高的進入障礙，間接保護了不具效率的既有廠商。課徵貨物稅對市場生產效率具有正面意義：貨物稅的課徵將使生產的邊際成本上升，即使市場中各廠商都面臨相同的成本上升壓力，具有效率廠商將較不受影響。貨物稅使具生產效率的廠商市場佔有率提高。這個結果與傳統經濟分析思維相反