Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We develop a simple model in which there is both interfirm (or intraproduct) and intrafirm (or interproduct) competition. The purpose is to develop a classificatoy framework in order to understand product‐range or diversification decisions alongside conventional competition. The equilibrium outcomes commonly involve a limited range of the available goods being produced. Deterrence equilibria and other strategic actions are also examined.