What Separates Bolivians From Each Other? A Survey Experiment of the Effects of Social Identities on Trust and Affection

This study examines the impact of historical and ascriptive social identities –such as ethnicity, region, and socioeconomic status– alongside newly formed partisan identities in Bolivia, using a behavioral survey experiment to measure trust and bias. Findings indicate that partisanship has emerged as a super-identity, consolidating various old unresolved cleavages and generating significantly stronger antagonism toward those with opposing voting preferences. On a one-to-ten scale, out-group bias among Incumbent and Opposition voters ranges from 0.90 to 1.73, compared to a statistically insignificant ethnic bias and a moderate regional bias of 0.55. Socioeconomic bias is also evident, with poorer groups exhibiting a 0.46 bias toward wealthier individuals. These results underscore the role of partisanship in amplif ying historical divides. We also studied how behavioral measures compare to self-report measures of affection, and our results show that traditional measures of affection display more fragmentation and polarization than behavioral measures. Importantly, we find no significant differences across identity groups in policy attitudes on issues such as democracy, property rights, welfare, gay marriage, or abortion, suggesting that partisan divides may stem more from a sense of being included or excluded by the group than from ideological disagreement.