<p>Interindividual social variation allows inferences linking social ties to fitness, but also raises questions about what drives the variation. We examined how group-level and individual factors (group size, availability of relatives, age, dominance rank) relate to inter-individual social variation in wild blue monkeys, and how these relationships reflect the social partners included in the analysis. Using focal follow data from adult females in 12 groups over 13 years, we examined five sociality measures: number of total, strong and weak ties, total tie strength, and tie evenness. We used linear mixed models to assess how group-level and individual factors influenced these measures, repeating the analysis for ‘peer’ partners (other adult females) only and for ‘non-peers’ (juveniles and adult males) to evaluate how including different partner sets affected the results. The number of available partners influenced all social measures regardless of partner criteria, while presence of relatives affected only the number of strong ties and total tie strength. Age and dominance rank affected number of ties to non-peer social partners, but had no significant effect on ties to peers. Infant presence increased total tie strength among peers, but reduced it for all partners and non-peers. The consistent effect of number of available partners conflicts with the hypothesis that time constraints limit sociality. Partner inclusion criteria influenced the strength and direction of some effects, showing that this analytical choice can influence conclusions, particularly when factors like age, rank, and maternity differentially affect ties to various partner classes.</p>