Worth the Weight: Conceptualizing and Measuring Homophily in Weighted Social Networks.

Homophily, or the tendency for social contact to occur among those who are similar, plays a crucial role in structuring our social networks. However, empirical research that tests for homophily almost always assumes it is an unvarying process that operates similarly for all social ties, regardless of their strength or level of intimacy. As data on weighted networks, or networks where ties are assigned quantitative measures of strength, become increasingly available, network researchers need to consider whether homophily processes operate differently for ties with varying weights. Here, I take this approach by first defining two variants of homophily that can arise in weighted networks: (1) strong tie homophily, or the tendency for ties with high values to cluster together similar peers, and (2) weak tie homophily, or the tendency for ties with low edge weights to connect same-attribute actors. I develop new parameters that can be included in valued ERGMs to distinguish between strong and weak tie homophily. Then, I use simulated data to empirically demonstrate the utility in differentiating between the two variants. I find that, in most networks, there are observable differences in the magnitude of strong versus weak tie homophily. Additionally, when there are low levels of clustering on the attribute of interest, distinguishing between strong and weak tie homophily often reveals that these processes operate in opposite directions. Since strong and weak ties carry substantively different implications, I argue that differentiating between the two homophily variants can uncover novel insights for a variety of social processes. [ABSTRACT FROM AUTHOR]