The authors argue that endogeneity of transportation costs needs to be taken into account when estimating the effect of distance on trade. Otherwise, the estimates of the distance effect may be biased and inconsistent. Endogenous transportation can introduce slope heterogeneity and spatial...

The authors argue that endogeneity of transportation costs needs to be taken into account when estimating the effect of distance on trade. Otherwise, the estimates of the distance effect may be biased and inconsistent. Endogenous transportation can introduce slope heterogeneity and spatial...

Typical panel data models make use of the assumption that the regression parameters are the same for each individual cross-sectional unit. We propose tests for slope heterogeneity in panel data models. Our tests are based on the conditional Gaussian likelihood function in order to avoid the...

This study investigates the effects of the transportation cost on the international trade. The first essay explores the effect of the transportation cost on the quality composition of trade. We derive a relationship between per unit and ad-valorem trade costs and the quality composition of trade...

The wage gap between skilled workers and unskilled workers expanded in the U.S. Based on the essential idea of Stolper and Samuelson (1941) and following the mandated wage method of Haskel and Slaughter (2003), this dissertation examines whether the reductions of U.S. import tariffs contributed...