Excess Entry, Vertical Integration, and Welfare
系统分析垄断性上游供应商对下游垄断竞争行业进行纵向一体化的福利效应，给出导致帕累托改进的充分条件，并揭示偏好多样性假设、过度进入与一体化福利效果之间的关系。
This article provides a systematic analysis of the welfare effects of vertical integration by a monopolist input supplier into a monopolistically competitive downstream industry. We give sufficient conditions on consumer preferences that lead to Pareto-improving vertical integration and demonstrate a close relationship between assumptions on preference for variety, excess entry in monopolistically competitive markets, and the welfare effects of vertical integration: Excess entry in downstream markets tends to give rise to Pareto-improving vertical integration. We extend the analysis to vertical oligopoly and access price regulation.