Ethnically fractionalized countries tilt toward less democratic, more presidential rule

Evidence

Table 1 confirms a positive correlation between the degree of polarization and the degree of insulation using both indices of ethnolinguistic fractionalization. More fractionalized systems are less democratic and more presidential. Table 2 presents some regressions where the dependent variable is the democracy index which, remember is defined as decreasing in democracy , confirming that the correlations indicated in Table 1 survive after controlling for several other economic and institutional variables. — Philippe Aghion, Alberto Alesina, and Francesco Trebbi, Endogenous Political Institutions, 167

Categorization

• XREF: Speaks to Acemoglu-Robinson-style debates on institutions vs. underlying social cleavages.
• SEED: Angle: does presidentialism cause polarization, or does polarization select for presidentialism?