研討日期	2020年12月28日上午10:20~ 12:30
研討地點	國立臺灣大學710討論室
主講題目 Title of the paper	Entry and mergers in oligopoly with firm-specific network effects
作者 Authors of the paper	Adriana Gama, Rim Lahmandi-Ayed, Ana Elisa Pereira
文獻出處 Journal, vol.(issue), pp	Economic Theory (2020) 70:1139–1164
主講人	許至乙
參加人員	許至乙、王光正、林燕淑、施姵全、梁文榮、澎正浩、黃鴻、丁虹仁、Bui Dang Long、Damiana Simanjuntak、陳彥勳、許雅媚、洪珮瑜、林虢楙、劉洋、蔡文鋒、周宗翰、呂文智
摘要 Abstract of the paper	This paper investigates the effects of exogenous entry on market performance, and the profitability and welfare effects of horizontal mergers in symmetric Cournot oligopolies with firm-specific network effects. With strategic substitutes in the Cournot part of the model, per-firm output is declining in the number of firms, but industry output, price, per-firm profit, consumer surplus and social welfare may go either way in response to entry. We identify respective sufficient conditions for each possibility. The counter-intuitive conclusions tend to require strong network effects. We study the scope for profitability of mergers and the associated welfare effects. In a general analysis, we provide a sufficient condition on inverse demand for a merger to be profitable, which amounts to requiring strong network effects. Under the condition that leads to higher industry output with entry, mergers are always social welfare-enhancing.