The effect of ethnic diversity on the participation in social groups: Evidence from trade unions

This paper advances the hypothesis that individuals in more ethnically fragmented societies, participate less in social groups. More precisely, the empirical analysis places the spotlight on trade unions and investigates whether ethnic diversity affects the decision of workers to participate in them. The analysis takes place along two layers: (a) country-level and (b) individual-level. First, building on a set of innovative instruments derived from the parasite-stress theory of values and sociality, our country-level analysis seeks to exploit exogenous sources of variation in ethnic diversity and establish a convincing causal relationship between ethnic diversity and trade union density across countries. In turn, we employ individual-level data from the European Social Survey (ESS) and investigate whether immigrants who cοme from more ethnically fragmented societies participate less in trade unions in their European countries of residence. Consistent with the prediction of the theory, both layers of the empirical analysis provide robust evidence of a negative, sizeable and highly significant effect of ethnic diversity on the participation in trade unions.