The paper provides new evidence on proxy indicators of market power for major European countries. The data shows moderately increasing average industry concentration over the last two decades, a considerably increasing proportion of high concentration industries, and an overall tendency towards...

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...