The paper presents a model of a software monopolist who benefits from a lagged network externality arising from consumers' feedback through the so-called bug-fixing effect. That is, the software producer is able to correct errors in the software code detected by previous users, improving her...

In this paper we study the welfare effect of a monopoly innovation. Unlike many partial equilibrium models carried out in previous studies, general equilibrium models are constructed and analyzed in greater detail. We discover that technical innovation carried out by a monopolist could...

This paper investigates strategic interactions between a private highway operator anda private transit operator who uses the same highway for its services. Heterogeneity oftravellers is taken into account by considering a continuous distribution of values of time.Demand elasticity arises from...

We study complementarity between product and process innovation in a monopoly setting. First we consider the possibility for the firm to alternatively invest only along one of the two directions and compare the incentives of process vs product innovation. Then we allow the firm to invest...

We model the optimal behaviour of a multiproduct monopolist investing both in process and in product innovation in a dynamic setting. Product innovation reduces the degree of substitutability between any two varieties. First, we find that R&D efforts increase in both directions as the number of...

We examine the persistence of monopolies in markets with innovations when the outcome of research is uncertain. We show that for low success probabilities of research, the incumbent can seldom preempt the potential entrant. Then the efficiency effect outweighs the replacement effect. It is vice...

Die Wirkung des Wettbewerbs von Medienunternehmen auf das Marktergebnis ist in einigen einschlägigen Modellen durchaus ambivalent. So haben - erstens - monopolistische Anbieter unter Umständen höhere Anreize, ein breitgefächertes Angebot zu erstellen. Zweitens ist das typische Kalkül der...