R/simEdgesNonSmooth.R

In SSDALab/dnr: Simulate Dynamic Networks using Exponential Random Graph Models (ERGM) Family

##' Implementation of simulation engine for dynamic networks without using smoothing estimates of change statistics.
##' @param start_network Initial list of networks 
##' @param inputcoeff coefficient vector
##' @param ns number of time points for simulation
##' @param model.terms model terms in formula
##' @param model.formula model formula (ergm)
##' @param graph_mode 'digraph' by default
##' @param group group terms
##' @param intercept intercept terms
##' @param exvar extraneous covariates
##' @param maxlag maximum lag
##' @param lagmat lag matrix
##' @param ylag lag vector for network lag terms
##' @param lambda NA
##' @param method 'bayesglm' by default
##' @param alpha.glmnet NA
##' @param paramout T/F parameter estimation is returned.
##' @return list:
##'   out_network: list of predicted networks
##'   coefmat: if paramout is TRUE, matrix of coefficients at all time.
##' @author Abhirup
##' @export
##' @examples 
##' \dontrun{
##' input_network=rdNets[1:6];
##' model.terms=c("triadcensus.003", "triadcensus.012", "triadcensus.102", "triadcensus.021D", "gwesp");
##' model.formula = net~triadcensus(0:3)+gwesp(decay=0, fixed=FALSE, cutoff=30)-1;
##' graph_mode='digraph';
##' group='dnc';
##' alpha.glmnet=1
##' directed=TRUE;
##' method <- 'bayesglm'
##' maxlag <- 3
##' lambda=NA
##' intercept = c("edges")
##' cdim <- length(model.terms)
##' lagmat <- matrix(sample(c(0,1),(maxlag+1)*cdim,replace = TRUE),ncol = cdim)
##' ylag <- rep(1,maxlag)
##' lagmat[1,] <- rep(0,ncol(lagmat))
##' out <- paramEdge(input_network,model.terms, model.formula,
##'                 graph_mode="digraph",group,intercept = c("edges"),exvar=NA,
##'                 maxlag = 3,
##'                 lagmat = lagmat,
##'                 ylag = rep(1,maxlag),
##'                 lambda = NA, method='bayesglm',
##'                 alpha.glmnet=1)
##' #
##' start_network <- input_network
##' inputcoeff <- out$coef$coef
##' nvertex <- 47
##' ns <- 10
##' exvar <- NA
##' tmp <- suppressWarnings(engineEdgeNS(start_network=start_network,
##'                      inputcoeff=inputcoeff,ns=ns,
##'                      model.terms=model.terms, model.formula=model.formula,
##'                      graph_mode=graph_mode,group=group,intercept=intercept,
##'                      exvar=exvar,
##'                      maxlag=maxlag,
##'                      lagmat=lagmat,
##'                      ylag=ylag,
##'                      lambda = NA, method='bayesglm',
##'                      alpha.glmnet=alpha.glmnet))}
##' 

engineEdgeNS <- function(start_network,inputcoeff,ns,
                          model.terms, model.formula,
                          graph_mode,group,intercept,
                          exvar,
                          maxlag,
                          lagmat,
                          ylag,
                          lambda = NA, method='bayesglm',
                          alpha.glmnet,
                          paramout = TRUE){
  nnetinput <- length(start_network)
  repfac <- nnetinput-maxlag
  nvertex <- network.size(start_network[[1]])
  nedges <- if(graph_mode=='digraph') nvertex*(nvertex-1)
  out_network <- list()
  coeflist <- list()
  lagmat[1,] <- rep(0,ncol(lagmat))
  for(ncount in 1:ns){
    print(ncount)
    out1 <- paramEdge(start_network,model.terms, model.formula,
                     graph_mode=graph_mode,group,intercept = intercept,
                     exvar=exvar,
                     maxlag = maxlag,
                     lagmat = lagmat,
                     ylag = ylag,
                     lambda = NA, method=method,
                     alpha.glmnet=alpha.glmnet,
                     paramout = paramout)
    inputmpleMat <- as.matrix(out1$mplemat[,-1])
    smmpleMat <- matrix(0,nedges,ncol(inputmpleMat))
    ## for(i in 1:repfac){
    ##   smmpleMat <- smmpleMat + inputmpleMat[(((i-1)*nedges+1):(i*nedges)),]
    ## }
    ## smmpleMat <- smmpleMat/repfac

    ## We do not smooth in this case, we only use the final value of change
    ## statistics.
    
    smmpleMat <-
        inputmpleMat[(((repfac - 1)*nedges + 1):(repfac*nedges)), ]
    
    inputpred <- smmpleMat%*%inputcoeff
    
    net.current <- start_network[[1]]
    X_t <- ungvectorize(inputpred,nvertex,graph_mode)
    net.current %n% "X" <- X_t
    net.current <- simulate(ergm(net.current ~ edgecov("X")))
    out_network[[ncount]] <- net.current
    for(i in 1:(nnetinput-1)){
      start_network[[i]] <- start_network[[i+1]]
    }
    start_network[[nnetinput]] <- net.current
    coeflist[[ncount]] <- out1$coef$coef
  }
  coefmat <- do.call(rbind,coeflist)
  return(list(out_network=out_network,coefmat=coefmat))
}