Based on a model of environmental quality differentiated products, we explore how an emission tax charged on consumers who choose an environment-unfriendly good, i.e. a consumer-based emission tax policy, affects the unit emission level of the product, the environment, and consumer and producer...

We examine the optimal R&D subsidy/tax policy under a vertically differentiated duopoly. In a significant departure from the existing work, we consider the case of asymmetric costs of product R&D where there is a small technology gap between firms. In our analysis, the endogeneity of quality...