Targeted search and the long tail effect
构建搜索模型解释长尾效应，研究搜索成本下降或搜索定向性提升如何影响商品多样性、销售集中度及消费者效用。
We develop a search model to explain the long tail effect. Search targetability, or the quality of search, is explicitly modelled. Consumers are searching for the right products within the right categories. As search costs decrease, or search targetability increases, additional variety of goods catering to long tail consumers will be provided, and the concentration of sales across different categories of goods decreases. The effects of a decrease in search costs or an increase in search targetability on consumer utility, prices, and profits depend on whether the type coverage increases. Decreases in search costs and increases in search targetability have different qualitative effects.