Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
In this note, the author offers the complete characterization of quality choices in a duopoly model of vertical product differentiation where firms simultaneously choose the quality of the product and then compete in prices. He thereby gives precise content to the 'principle of differentiation' in models of vertical product differentiation, which completes and amends previous results on the subject. Copyright 1996 by Blackwell Publishing Ltd.