We revisit Maxwell's (1998) analysis to show that MQS regulation has no effects on the high-quality firm's incentive to adopt a more efficient technology in a vertically differentiated duopoly with fixed costs of quality improvement and full market coverage

We examine a vertically differentiated duopoly where firms invest in process and product innovation and then compete in prices under full market coverage. We show that (i) process and product innovation are complements (substitutes) for the low-quality (high-quality) firm; (ii) the firm which is...

We investigate the timing of adoption of product and process innovation by using a differential game in which firms may invest in both activities. We consider horizontal product innovation that reduces product substitutability, and process innovation that reduces marginal cost. First, we...

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...