Tie-formation mechanisms like homophily, reciprocity, transitivity, and preferential
attachment operate to varying degrees across contexts. Romantic ties tend to be
homophilous by age, education, and ethnicity, and to remain dyadic. Scientific citations, in
contrast, fall into highly unequal preferential attachment patterns. Triangulation is nearly
absent in advice and patronage networks but features prominently in friendship ties.
Building on relational sociology and field theory, we argue that such variation in patterns of …