cohesion is developed. Changes in technological cohesion can then be decomposed into selection, entry and exit effects … revealing that the change in technological cohesion is not only due to the entry and exit of related industries but employment … less likely to exit a metropolitan industry portfolio if they are technologically related to those industries. Third, based …

pattern (varieties and markets) of existing firms in combination with entry/exit of firms. The empirical results are …This paper develops a framework to appreciate the observed heterogeneity of firm size distributions and the entry and … exit of products and firms associated with it. It is based on a model where new products are introduced by innovating firms …