“…1 The rst applications of Pólya urns in economics date back to the seminal works by Simon (1955), Ijiri and Simon (1975) and Ijiri and Simon (1977) on rm size distribution. Since then, Pólya urn processes have been employed in several domains of economics, and in particular in the analysis of technical change (Arthur et al, 1987;Arthur, 1989;Dosi et al, , 2019 and industry dynamics (Fu et al, 2005;Bottazzi and Secchi, 2006a;Bottazzi et al, 2007;Riccaboni et al, 2008). 2 However, to the best of our knowledge, so far there is no application of Pólya urns to the analysis of international trade dynamics.…”