Ancestral diversity and performance: Evidence from football data

The theoretical impact of diversity on performance is ambiguous since it leads to costs and benefits at the collective level. In this paper, we empirically assess the connection between ancestral diversity and the performance of sports teams. Focusing on football (soccer), we built a novel dataset of national teams of European countries that have participated in the European and World Championships since 1970. The ancestral diversity of national teams is measured from genetic distance scores within the team, based on information on every player's origins. Origins are recovered using a matching algorithm based on family names. Performance is measured at the match level. Identification of the causal link relies on an instrumental variable strategy based on past immigration at the country level about one generation before the competition. Our findings indicate a positive causal link between ancestral diversity and national teams' performance. We find that a one-standard increase in diversity leads to a significant increase in the goal difference of 0.77 to 1.79 goals per match (about a 1.30 goal difference per match).