R/likelihood.R

In SAcmu/LLSM: Package to Fit Longitudinal Latent Space Model

#' @title Function to compute the logistic log-likelihood in the latent space model
#' 
#' @description \code{likelihood} returns the logistic log-likelihood in LSM
#' 
#' @details \code{likelihood} returns the logistic log-likelihood in LSM 
#' (for both directed and undirected networks)
#' @param Y the adjacency matrix of binary ties information 
#' @param Z the matrix of latent positions 
#' @param intercept the intercept in the model
#' @export
#' 

likelihood <-
function(Y,Z,intercept)
{
  nn = nrow(Y)
  dd = ncol(Z)
  return(FullLogLik(YY=Y, ZZ=Z, intercept=intercept, nn=nn, dd=dd))
    # 
    # llik = 0
    # Zdist = as.matrix(dist(Z)) #latent distance
    # nn = nrow(Y)
    # #compute loglikelihood for the entries of Y except the diagonal
    # for(ii in 2:nn){
    #     for(jj in 1:(ii-1)){
    #         dij = Zdist[ii,jj]
    #         pij = logitInverse(intercept,dij)
    #         if(Y[ii,jj] == 1){
    #             llik = llik + (Y[ii,jj])*log(pij) }
    #         if(Y[ii,jj] == 0){
    #             llik = llik + (1-Y[ii,jj])*log(1-pij)}
    #         if(Y[jj,ii] == 1){
    #             llik = llik + (Y[jj,ii])*log(pij) }
    #         if(Y[jj,ii] == 0){
    #             llik = llik + (1-Y[jj,ii])*log(1-pij)}
    #     } }
    # return(llik)	
}