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 doubts on the robustness of Coe and Helpman’s findings. We show that Keller’s “random” weights are essentially simple averages with a random error. We derive alternative random weights and present regressions showing that when they are used to define the foreign R&D capital stock, the estimated international R&D spillover estimates are nonexistent, as would be expected.
Ms. Margaux MacDonald, Mr. Roberto Piazza, Johannes Eugster, and Ms. Florence Jaumotte
Based on an empirical gravity model of sectoral bilateral trade, we uncover three features of bilateral trade balances. First, the difficulty of gravity models in fitting the observed level of bilateral balances is likely due to the presence of unobservable bilateral trade costs. Second, the model fit improves drastically when we focus on changes over time of the balances. Third, using a log linear approximation we show that changes in bilateral trade balances over the past two decades were driven almost entirely by changes in the same macro factors that determine countries’ aggregate balances – changes in bilateral trade costs, including tariffs, played therefore only a negligible role. This conclusion provides new support for the view that bilateral balances are, for practical purposes, not relevant to the conduct of macroeconomic policy.
Recent empirical research finds that pairs of countries with stronger trade linkages tend to have more highly correlated business cycles. We assess whether the standard international business cycle framework can replicate this intuitive result. We employ a three-country model with transportation costs. We simulate the effects of increased goods market integration under two asset market structures, complete markets and international financial autarky. Our main finding is that under both asset market structures the model can generate stronger correlations for pairs of countries that trade more, but the increased correlation falls far short of the empirical findings. Even when we control for the fact that most country-pairs are small with respect to the rest of the world, the model continues to fall short. We also conduct additional simulations that allow for increased trade with the third country or increased TFP shock comovement to affect the country pair's business cycle comovement. These simulations are helpful in highlighting channels that could narrow the gap between the empirical findings and the predictions of the model.
This paper considers the impact on trade of preferential arrangements in Europe since the 1950s. Using a first difference version of the gravity model, we find that the EEC and EFTA altered the pattern of international trade. We also find evidence of trade diversion in several cases, notably that of the EEC in the 1960s.