When analyzing panel data using regression models, it is often reasonable to allow for time-varying covariate effects. We propose a novel approach to modelling timevarying coefficients in panel data regressions, which is based on penalized regression techniques. To illustrate the usefulness of...

There is a well-established literature on border effects covering trade between regions separated by a land border; however that literature has not so far considered the case of regions separated by a sea border. Whilst the former is typically studied as a political border that affects adjacent...

This paper compares various estimation techniques used to determine the impact of distance and borders on international trade. The results consistently confirm the significantly negative distance effect, while the border effect, measured by evaluating whether intra-continental trade exceeds...

The "distance effect" measuring the elasticity of trade flows to distance has been rising since the early 1970s in a host of studies based on the gravity model, leading observers to call it the "distance puzzle" . This paper reviews the evidence and explanations. Using an extensive data set of...

Technical progress can be expected to reduce transport costs over time, yet most studies of bilateral trade based on the gravity model find distance effects to be increasing rather than decreasing. We investigate countries' openness to international trade (the ratio of exports plus imports to...