International R&D Spillovers : Technology Transfer vs. R&D Synergies

We estimate a model of international technological spillovers that allows for both international and inter-sectoral technology transfer, as well as international and intersectoral synergies in research and development (R&D). Furthermore we allow for a dynamic interaction in explaining total factor productivity (TFP). Relative to the existing literature, our model enables us make a judgment on the relative importance of the channels of international technology transmission. We find that direct technology transfer is positive while there are negative R&D spillovers. However, since R&D is found to positively affect TFP in own sector, the model implies that after accounting for both R&D and TFP spillovers, there is a total positive impact of R&D on TFP in the same sector while the overall impact of R&D on TFP in other sectors and countries is negative. Our results indicate that, by not distinguishing among different channels of transmission, some models previously estimated in the literature may suffer from omitted variable bias