We estimate a gravity model to address the question of whether Africa’s bilateral trade with industrial countries is “unusual” compared with other developing country regions. Our main finding is that the unusually low level of African trade is explained by economic size, geographical...

Keller (1998) reexamines Coe and Helpman’s (1995) analysis of international R&D spillovers focusing on the weights used to define the foreign R&D capital stock. Keller creates “random” weights and shows that they give rise to positive estimates of international R&D spillovers, casting...

The empirical analysis in ""International R&D Spillovers"" (Coe and Helpman, 1995) is first revisited by applying modern panel cointegration estimation techniques to an expanded data set that we have constructed for the purpose of this study. The new estimates confirm the key results reported in...