Quality‐improving R&D and merger policy in a differentiated duopoly: Cournot and Bertrand equilibria

We combine a model of product research and development (R&D) and technological spillover with the concept of technological distance and examine horizontal mergers in a duopolistic market with R&D. The results are fourfold. First, a merger can better encourage R&D investment than the competition case. Second, with a small degree of product differentiation (PD), the merger criterion under the Cournot duopoly is stricter than that of the Bertrand case. By contrast, with a moderate or large degree of PD, the opposite is true. Third, with a small technological distance, a merger should be allowable. Finally, with a small degree of PD and moderate technological distance, a merger should be allowable.