James Anderson, Yoto Yotov, 20 December 2020

The gravity equation of international trade raises several empirical puzzles relating to the decreasing impact of distance, the declining trade-related costs of bilateral trade, and the estimation of trade elasticities. This column introduces a new, ‘short-run gravity’ model which simultaneously resolves all three of the above-mentioned puzzles. The model estimates a 14% decline in the distance elasticity and shows that capacity reallocation raised world manufacturing trade by 75% between 1998 and 2006. Finally, an estimated structural parameter implies that the short-tun trade elasticity is about one-fourth of its long-run counterpart. 

Tomoya Mori, Jens Wrona, 16 August 2019

The gravity equation has often been used to explain trade between regions or cities within countries. But it assumes that the distribution of industries is exogenous. This column explains how trade estimates are affected if we assume that large, centrally located cities attract more industries whose firms are more likely to export to other cities. Japanese data show exports from these cities are systematically underpredicted by aggregate gravity estimations, as the theory predicts.

Erik Brynjolfsson, Xiang Hui, Meng Liu, 16 September 2018

Recent years have seen dramatic progress in the predictive power of artificial intelligence in many areas, including speech recognition, but empirical evidence documenting its concrete economic effects is largely lacking. This column analyses the effect of the introduction of eBay Machine Translation on eBay’s international trade. The results show that it increased US exports on eBay to Spanish-speaking Latin American countries by 17.5%. By overriding trade-hindering language barriers, AI is already affecting productivity and trade and has significant potential to increase them further.

Vincent Bouvatier, Gunther Capelle-Blancard, Anne-Laure Delatte, 11 September 2018

Tax havens are estimated to concentrate 8% of global private financial wealth, reducing annual global tax revenues by about $200 billion. This column uses new country-by-country regulatory data on the foreign commercial presence of EU banks and compares it against gravity model predictions to examine the contribution of EU banks to tax evasion. It finds that bank activity in tax havens is three times larger than what is predicted by the gravity model, and that British and German banks are particularly present in tax havens. 

Morgan Kelly, Cormac Ó Gráda, 18 August 2018

Little is known about migration to cities in the era before railways. The column uses data on the origins of women arrested for prostitution in Paris in the 1760s, women registered as prostitutes in the 1830s and 1850s, men holding identity cards during the French Revolution, as well as everyone buried in 1833 to examine patterns of migration. Migration was highest from areas with high living standards, and the impact of distance fell as transport improved. Distance was a stronger deterrent to females than to males, consistent with more limited employment opportunities for women.

Hylke Vandenbussche, William Connell, Wouter Simons, 27 November 2017

Global value networks make it difficult to evaluate the trade impact of Brexit. Using a new model of trade that accounts for the indirect effect of these networks, this column delivers fresh bad news for the UK, and for the rest of Europe. Brexit cuts GDP more, and costs more jobs, if we also consider global value chains. A hard Brexit would destroy four times as much GDP, and four times as many jobs throughout Europe, as a soft Brexit.

Natalie Chen, Dennis Novy, 27 January 2009

This column assesses trade costs for manufacturing industries in the EU. It demonstrates that, although tariffs on trade within the EU were abolished decades ago, significant barriers remain, and countries continue to integrate. Today, the most substantial policy-induced costs are technical barriers to trade, such as packaging and labelling requirements.

Robert Dekle, Jonathan Eaton, Samuel Kortum, 27 August 2008

A correction of international imbalances seems inevitable. What will that entail? This column presents estimates of the changes in trade flows required to rebalance the world’s current accounts and analyses which countries will bear the burdens of adjustment.

CEPR Policy Research