Two-sided network effects in card payment systems are analysed under different market structures, e.g., competition, one-sided monopoly, bilateral monopoly and duopoly; with and without an interchange fee; for the so-called Baxter's case of non-strategic merchants. A partial ranking of market...

Using a sample of 96 mergers notified to the EU Commission and logit regression techniques, we analyse the Commission's decision process. We find that the probability of a phase 2 investigation and of a prohibition of the merger increases with the parties' market shares. The probability...