"In this paper we [the authors] present a model that addresses the issue of the uneven distribution of employment opportunities over low- and high-skilled workers in a context of skill-biased endogenous technical change. In our model, technical change consists in part of product innovation. There is also process innovation to the extent that new products can be produced in two different ways, either using high-skilled workers, or using low-skilled workers after adapting the production process of a new product." (Quoted from paper)