We find that ethnic Chinese networks, proxied by the product of ethnic Chinese population shares, increased bilateral trade more for differentiated than for homogeneous products. This suggests that business and social networks have a considerable quantitative impact on international trade by helping to match buyers and sellers in characteristics space, in addition to their effect through enforcement of community sanctions that deter opportunistic behavior. For trade between countries with ethnic Chinese population shares at the levels prevailing in Southeast Asia, the smallest estimated average increase in bilateral trade in differentiated products attributable to ethnic Chinese networks is nearly 60%.

Improved information allows home firms to rule out more potential foreign trade partners in advance of attempting to form a match. The increased responsiveness to country wage or goods price differentials resulting from this better first cut causes the general-equilibrium elasticity of substitution between national labor forces or the Armington elasticity of substitution between domestic and imported output to increase. Further results include an increase in the elasticity of domestic labor demand, an increase in the extent to which reductions in conventional trade barriers equalize national wages, and reduced “natural protection” for domestic producers.