Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
This paper proposes a reduced form model of dynamic duopoly in the context of heterogeneous innovations framework. Two agents invest into expansion of variety of available products and into the improvement of quality of existing products simultaneously. Every newly introduced product has its own dimension of quality-improving innovations and there is a continuum of possible new products. In the area of quality innovations the costless imitation effect is modelled while in the area of variety expanding innovations agents are cooperating with each other. As a result the specialization of innovative activity is observed. This specialization arises from strategic interactions of agents in both fields of innovative activity and is endogenously defined from the dynamics of the model.