Table S1.

Defection model: Effect of intergroup conflict on subgroup cohesion

Term	Estimate	SE	CIlower	CIupper	χ2*	P
Intercept	−0.475	0.241	−0.962	−0.026	–	–
Intergroup conflict†	−1.732	0.446	−2.586	−0.809	13.484	<0.001
Group‡,§	−1.358	0.671	−3.113	−0.311	4.700	0.030
Proximity¶	0.184	0.201	−0.190	0.587	0.829	0.363

Statistically significant results (P ≤ 0.05) appear in bold.

^*Degrees of freedom are 1.

^†,^‡χ² and P values refer to comparison with the reference categories ^†control and ^‡East group.

^§Group identity was associated with large uncertainty due to the small sample size of South group.

^¶z-transformed, mean ± SD of the original variables: 72.57 ± 24.19 (range 5 to 99).