*My research focuses on measuring the inequality of ordinal variables. In this presentation, I will reiterate the problem highlighted by Alisson and Foster (2004) when trying to measure the inequality of such variables. I will discuss the solutions proposed in the literature, focusing specifically on the article by Gravel and al (2021), in order to introduce new measurement tools.

**Trade continues to be impeded by borders and distance to a puzzling degree. An influential (but untested) theory attributes this underperformance of trade to an insufficient number of 'pioneer' firms that create new trade links. This paper provides the first causal evidence of the effect of individual pioneers on aggregate trade and growth. I compile all 1.4 million sea captain voyages between Baltic Sea ports and the rest of the world from 1500 to the 1850s. For identification, I exploit events at sea that affect individual captains, such as the temporary obstruction of ports by sea ice, which forces captains to pioneer new ports. I find that the pioneering of an individual captain spills over to the total trade of a town, increasing it by 2 to 4\%. These effects are even greater when sea ice forces captains to become pioneers. I show that this is due to the pioneering of more distant ports in terms of kilometers, religion, language, and product mix. In the absence of forced experimentation, pioneers select \textit{less} distant ports, which tend to be less successful. Together, these findings demonstrate the effects of individuals (and their behavioral biases) on aggregate trade and growth. For policy, this suggests that even small interventions that promote pioneering in distant destinations can have large effects.