This paper develops a new framework for studying multiproduct intermediaries when consumers demand multiple products and face search frictions. We show that a multiproduct intermediary is profitable even when it does not improve consumer search efficiency. In its optimal product selection, it stocks high-value products exclusively to attract consumers to visit, then profits by selling non-exclusive products which are relatively cheap to buy from upstream suppliers. However, relative to the social optimum, the intermediary tends to be too big and stock too many products exclusively. As applications we use the framework to study the optimal design of a shopping mall, and the impact of direct-to-consumer sales by upstream suppliers on the retail market.

中文翻译：

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多产品中介

当消费者需要多种产品并面临搜索摩擦时，本文开发了一个新的框架来研究多产品中介。我们表明，即使不提高消费者搜索效率，多产品中介也是有利可图的。在其最优的产品选择上，它专门储备高价值的产品来吸引消费者的光顾，然后通过销售从上游供应商那里购买相对便宜的非独家产品来获利。然而，相对于社会最优，中介往往规模过大，且只储备了过多的产品。作为应用程序，我们使用该框架来研究购物中心的优化设计，以及上游供应商直接面向消费者的销售对零售市场的影响。