This paper surveys the measurement of trade costs: what we know and don't know but may
usefully attempt to learn. Partial and incomplete data on direct measures of costs go with …

Gravity has long been one of the most successful empirical models in economics.
Incorporating deeper theoretical foundations of gravity into recent practice has led to a richer …

This chapter focuses on the estimation and interpretation of gravity equations for bilateral
trade. This necessarily involves a careful consideration of the theoretical underpinnings …

For over 40 years, the gravity equation has been a workhorse for cross-country empirical
analyses of international trade flows and—in particular—the effects of free trade agreements …

Summary 1 Humans have traded and transported alien species for millennia with two
notable step‐changes: the end of the Middle Ages and beginning of the Industrial …

Micro-level data have had a profound influence on research in international trade over the
last ten years. In many regards, this research agenda has been very successful. New …

In the last two decades, improvements in materials, sensors and machine learning
technologies have led to a rapid extension of electronic nose (EN) related research topics …

The striking growth in the trade share of output is one of the most important developments in
the world economy since World War II. Two features of this growth present challenges to the …

Corruption and imperfect contract enforcement dramatically reduce international trade. This
paper estimates the reduction using a structural model of import demand in which insecurity …

A large and growing share of world trade travels by air. We model exporters' choice between
fast, expensive air cargo and slow, cheap ocean cargo, which depends on the price …