The Competitive Effects of Entry: Evidence from Supercenter Expansion
利用11年间沃尔玛开店数据与周度杂货交易数据，研究发现超级中心进入导致1英里内现有超市收入骤降16%，但对价格无因果影响。
Coupling weekly grocery transactions with the exact location and opening date of Walmarts over an 11-year period, we examine how Supercenter entry affects prices and revenues at incumbent supermarkets. We find that entry within 1 mile of an incumbent causes a sharp 16 percent drop in revenue, a competitive effect that decays quickly with distance. Surprisingly, despite large cross-sectional differences in supermarket prices by exposure to Walmart, our findings also indicate that Supercenter entry has no causal effect on incumbent prices. This result is robust across many dimensions, including a lack of price response for individual products, and across brands within a category.