The neglected effects of demand characteristics on the sustainability of collusion

According to standard IO models, the parameters that characterize market demand (intercept, slope, and elasticity) and technology (the level of symmetric marginal costs) do not play any role in defining the sustainability of collusive behaviors in Bertrand oligopolies. This paper modifies this counterintuitive result by showing that all of the aforementioned factors do indeed matter when prices are assumed to be discrete rather than continuous. The sign of these effects is clear. Their magnitude varies greatly; i.e., in some cases, it is totally negligible, while in others, it becomes extremely relevant.