Privacy in Search Markets

Heterogeneous search costs enable price discrimination, which I study in the canonical Wolinsky (1986) sequential search setting. Firms observe a public signal of a consumer’s search cost before posting a personalized price. The welfare effects of search-cost-based price discrimination depend on the distribution of search costs. For sufficiently small search costs, all consumers participate, and price discrimination reduces consumer surplus. When search costs are sufficiently dispersed, price discrimination reduces participation; its effect on consumer surplus is ambiguous and decomposed into three forces. This decomposition guides optimal information design: the consumer-surplus-maximizing policy is a binary signal that separates low- and high-search-cost consumers.