This repo constitutes an R package, and contains data and tools for the triadic analysis of affiliation networks.

The paper Triadic analysis of affiliation networks makes a case for adopting a batch of triad-based tools for the study of (bipartite) affiliation networks. Most of the tools used therein are included in this package, which is built mostly on the igraph package. No new classes have been defined yet, but several back-end functions are written in C++ without reference to the igraph library. Any suggestions would be welcome.

The package is not yet on CRAN; it can be installed using the devtools package:

devtools::install_github("corybrunson/bitriad")

The package implements several tools from the paper, most importantly

• triad_census(), which surveys the triads of an affiliation network and returns the census in a specified scheme; and
• triad_closure(), which surveys the wedges of an affiliation network and returns either global or local proportions of wedges that are closed.

The parameters for these functions, in particular the census schemes and the definitions of wedge and closure, are thoroughly documented in help(triad_census) and help(triad_closure). Both functions pass to their corresponding functions in igraph when the input graph is not an affiliation network.

Empirical affiliation networks from the following sources are included as datasets:

• Davis(, Davis), Gardner, Gardner(, and St Clair Drake)'s Deep South: A Social Anthropological Study of Caste and Class, p. 148 (women_group) and p. 209 (women_clique);
• Scott and Hughes' The Anatomy of Scottish Capital, specifically Table 2, covering 1920-21 (scotland1920s);
• Galaskiewicz's Social Organization of an Urban Grants Economy, specifically a subset reproduced in Faust's "Centrality in affiliation networks" (minneapolis1970s);
• Barnes and Burkett's "Structural Redundancy and Multiplicity in Corporate Networks" (chicago1960s);
• Noordin Top Terrorist Network Data, using meetings (nmt_meetings) and organizations (nmt_organizations) as events;
• Fischer's Paul Revere's Ride, Appendix D, as used in Han's "The Other Ride of Paul Revere" (whigs).

The vignette southern_women outlines an analysis of women_clique and women_group using the censuses, some clustering coefficients, and other tools.

The full documentation is built into a bitriad website using pkgdown.