客户重叠与转移比率

摘要

We define the concept of customer overlap of product j with product k as the share of j’s customers who buy k. We argue that, in appropriate contexts, customer overlaps are an excellent proxy for diversion ratios, a useful and popular way to summarize competition between sellers of substitute products. Unlike diversion ratios, which are often challenging to estimate, customer overlaps are straightforwardly observed in many datasets. We show theoretically, and validate empirically, the close connection between customer overlaps and diversion ratios. We illustrate the potential use of customer overlap in contexts where estimation of diversion ratios could be prohibitive.