A Simple Proof of Sweezy's 'Kinked-Demand' Conjecture.

This paper identifies conditions on the substitutability of product varieties, market price, and the number of firms in the industry, that ensure the existence of the conjectural equilibrium postulated by P. M. Sweezy (1939) and referred to as the "kinked demand curve." The authors show that the equilibrium thus identified will, under certain conditions, be robust in the face of changes in cost. Copyright 1992 by Scottish Economic Society.