Using Network and Spatial Data to Better Target Overdose Prevention Strategies in Rural Appalachia

摘要

Example network data for this analysis. Eight directed ties. Of these, 4 are reciprocal ties (c, d, g, and h) and 4 are unreciprocated, or one-directional ties (a, b, e, and f). For the analyses presented in this paper, we assumed that a relationship between two individuals existed if at least one person in the pair indicated knowing the other person in the pair. For example, in , individual 1 reported knowing individual 2, but individual 2 did not report knowing individual 1. The symmetrized or undirected version of ( ). For the dyadic analyses, which focused on relationships, we assumed (as shown in b) that if at least one individual reported a relationship to another, that the tie was reciprocated. Thus, shows two arrows between these individuals (a and a ). The dyadic analysis in this example would therefore consists of 12 ties and an individual-level analysis would include 6 individuals. As displayed in , this means that there are two one-degree paths (i.e., one in either direction) between all connected nodes in the network. Dyadic analyses require that there be information on the relationship between the two individuals. In cases like the relationship between individual 2 and individual 4, each individual provided information about the relationship with the other and this information may not agree. For example, the relationship information reported by individual 2 (represented by tie d) and by individual 4 (represented by tie c) may be different. We therefore used information reported about the relationship between 4 and 2 by individual 4 (represented by tie c) for analyses interested in the directed path between 4 and 2; and information about the relationship reported by 2 (represented by tie d) for the directed path between 2 and 4. In scenarios where only one individual in the pair reported knowing the other (i.e., the tie represented by between individuals 1 and 2), we used the information about the relationship reported by individual 1 for the path represented by both a and a in ( ). For the egocentric analyses, we assumed that individuals 1 and 3 had only one first-degree network member, individuals 5 and 6 had two first-degree network members, and individuals 2 and 4 had 3 first-degree network members