collaborate in R&D is increasing in R&D productivity. The key findings of the theoretical model are tested using German innovation … survey data for the service sector. A simultaneous model for cooperation choice and innovation expenditures shows that R …&D cooperation has a weakly significant positive effect on innovation expenditures. The empirical results broadly support the …

R&D cooperation only considered process innovation, the model presented here also takes product innovation into account …. It is shown that the optimal R&D investment has virtually the same structure for both process and product innovation. The …