Oligopoly and Consistent Conjectural Variations

This article examines "consistent" conjectural variations in an oligopoly model with a homogeneous product. A conjectural variation is consistent if it is equivalent to the optimal response of the other firms at the equilibrium defined by that conjecture. When the number of firms is fixed, we find that competitive behavior is consistent when marginal costs are constant, but that when marginal costs are rising, the consistent conjectural variation will be between competitive and Cournot behavior. Finally, if we allow free entry and redefine consistency to account for such, then only competitive behavior will be consistent.