The effects of partially cooperating firms are examined in N-firm oligopolies. The Herfindahl-Hirschmann Index is assumed to detect the violation of the antitrust regulation by the firms, and based on this assumption a piece-wise differentiable dynamic system can be developed. The firms stop...

A general framework of partial cooperation and shareholding interlocks in oligopolies is first introduced, and then the best responses of the firms are determined. The monotonic dependence of the equilibrium industry output on the cooperation levels of the firms is proved. Conditions are given...

The Herfindahl--Hirschman Index is one of the most commonly used indicators to detect anticompetitive behaviour in industries. In fact, an increase in the value of the index is usually interpreted as an indicator of actions which may lessen competition or even create a monopoly. In this article...