In this paper, we undertake an in-depth inquiry into the nature of sharing externalities, and study how they affect the market outcome. We show that the key thing for understanding sharing externalities is the interplay between two forces: the specialization/complexity effect, on the one hand,...

We develop a two-sector model of monopolistic competition with a differentiated intermediate good and variable elasticity of technological substitution. This setting proves to be well-suited to studying the nature and origins of external increasing returns. We disentangle two sources of scale...