Includes functions for estimation of the (multilevel) p2 model (van Duijn, Snijders and Zijlstra (2004) doi:10.1046/j.0039-0402.2003.00258.x), more specifically the adaptive random walk algorithm (Zijlstra, van Duijn and Snijders (2009) doi:10.1348/000711007X255336), for the estimation of the j2 model (Zijlstra (2017) doi:10.1080/0022250X.2017.1387858), and for their bidirectional counterpart, b2.
Zijlstra, B.J.H., Duijn, M.A.J. van, and Snijders, T.A.B. (2009). MCMC estimation for the p2 network regression model with crossed random effects. British Journal of Mathematical and Statistical Psychology, 62, 143-166. Zijlstra, B.J.H. (2017). Regression of directed graphs on independent effects for density and reciprocity. Journal of Mathematical Sociology, 41(4), 185-192.
Examples
# create a very small network with covariates for illustrative purposesS <- c(1,0,1,0,1,1,0,1,0,1)REC <-(S*-1)+1D1 <- matrix(c(0,1,0,1,0,1,0,1,0,1,0,0,0,1,0,1,0,1,0,1,1,1,0,0,1,0,0,0,0,0,1,1,1,0,1,0,0,0,0,1,1,0,1,0,0,1,1,0,1,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,1,0,1,0,1,1,0,0,0,0,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,1,1,1,0,0,0,0,0), ncol=10)D2 <- abs(matrix(rep(S,10), byrow =FALSE, ncol=10)- matrix(rep(REC,10), byrow =TRUE, ncol=10))R <- D1*t(D1)Y <- matrix(c(0,1,1,1,1,1,0,0,1,1,0,0,0,1,1,1,0,0,1,0,1,1,0,1,1,1,0,0,1,1,1,1,1,0,1,1,0,1,1,0,1,1,1,1,0,1,1,0,1,1,0,1,1,1,1,0,1,1,1,0,1,0,1,0,1,1,0,1,0,1,0,1,1,1,0,1,1,0,1,1,1,0,1,0,1,0,1,1,0,1,1,1,1,0,0,1,1,1,1,0), ncol=10)# estimate p2 modelp2(Y,sender=~ S, receiver =~ REC, density =~ D1 + D2, reciprocity=~ R, burnin =100, sample =400, adapt =10)# Notice: burn-in, sample size and number of adaptive sequenses are # much smaller than recommended to keep computation time low.# recommended code: ## Not run:p2(Y,sender=~ S, receiver =~ REC, density =~ D1 + D2, reciprocity=~ R)## End(Not run)