In oligopoly markets players have the incentive for collusion to increase their profit
as this is typically more lucrative than a competitive attitude. As a counterpoint
to the creation of cartels, legislative institutes monitor economic behaviour, within
the EU the European Commission is responsible. Cartel activity is very difficult to
detect and therefore some of the cooperations may have a very long lifetime. Our theoretical
research investigates that if a cartel is established on an oligopolistic market,
certain market tendencies or their temporal variation relative to competitive dynamics
would change. Thus the existence of a cartel can be demonstrated by the changes in
market share and the speed, amplitude and direction of that movement.
