This paper introduces a number of game-theoretic tools to model collusive agreements among firms in vertically differentiated markets. I firstly review some classical literature on collusion between two firms producing goods of exogenous different qualities. I then extend the analysis to a...

The seminal paper by Salant, Switzer and Reynolds (1983) showed that merger in a standard Cournot framework with linear demand and linear costs is not profitable unless a large majority of the firms are involved in the merger. However, many strategic aspects matter for firm competition such as...

This chapter surveys recent models of coalition and network formation in a unified framework. Comparisons are drawn among various procedures of network and coalition formation, involving simultaneous and sequential moves. The survey also covers models of group and network formation by farsighted...

Pairing Games or Markets studied here are the non-two-sided NTU generalization of assignment games. We show that the Equilibrium Set is nonempty, that it is the set of stable allocations or the set of semistable allocations, and that it has several notable structural properties. We also...

We provide a new proof of the non-emptiness of approximate cores of games with many players of a finite number of types. Earlier papers in the literature proceed by showing that, for games with many players, equal-treatment cores of their "balanced cover games", which are non-empty, can be...

Ordinally single-peaked preferences are distinguished from cardinally single-peaked preferences, in which all players have a similar perception of distances in some one-dimensional ordering. While ordinal single-peakedness can lead to disconnected coalitions that have a "hole" in the ordering,...