Assortment decisions are key strategic instruments for firms responding to local market conditions. We assess this claim by studying the effect of a national merger between two large Dutch supermarket chains on prices and on the depth as well as composition of assortment. We adopt a...

We study the effect of a merger between two Dutch supermarket chains to assess its effect on the depth as well as composition of assortment. We adopt a difference-in-differences strategy that exploits local variation in the merger's effects, controlling for selection on observables through a...

We present a general and tractable oligopoly model of multi-sided platforms with endogenous side and platform choices of heterogeneous end-users, considering any mix of single-homing and multi-homing platforms and in which participating on one side could preclude doing so on others. We show the...