We propose a framework for analyzing spatial competition between retailers of different formats. Our approach yields localized measures of concentration and store-level diversion ratios that can be used to prospectively evaluate mergers in highly differentiated retail markets. Our method does...

Yahoo! Research partnered with a nationwide retailer to study the effects of online display advertising on both online and in-store purchases. We use a randomized field experiment on 3 million Yahoo! users who are also past customers of the retailer. We find statistically significant evidence...