Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
The paper deals with three issues that are central to the combined use of intranational and international data to estimate the economic consequences of national borders. The first issue concerns the measurement of trading distances for transactions that take place within a country or region. The second issue relates to the use of coefficients from an estimated gravity relationship to express the border effect in terms of an equivalent distance. The author proposes a technique to avoid problems that have beset earlier attempts to do this. The third issue is the need to ensure that the border and distance effects are estimated independently.