Tying in Two‐Sided Markets with Multi‐Homing: Corrigendum and Comment
指出Choi（2010）关于双边市场中捆绑销售论文的两个问题，并提出修正方案：一是无捆绑时的均衡需要更严格条件，二是捆绑时的均衡分析忽略了有利可图的偏离。通过模拟发现，捆绑在有利可图时能提升福利，与Choi的结论一致。
Abstract We identify two issues in Choi's [2010] paper on tying in two‐sided markets published in this Journal, and provide solutions to both of them. First, we point out that the equilibrium in the absence of tying requires more restrictive conditions and does not satisfy a natural equilibrium refinement criterion. We offer an alternative timing structure that validates the equilibrium derived in Choi [2010] under the conditions provided there. Second, we show that his equilibrium analysis with tying ignores a profitable deviation. We rectify this analysis under our alternative timing structure and derive the (mixed‐strategy) equilibrium with tying. We also show by means of simulations that tying is welfare‐enhancing whenever it is profitable, which is consistent with the main finding in Choi [2010].