simulate.RL: The Relocating Links algorithm

In nem: Generating networks with selected blockmodel

Description

The function generate random network considering the selected types of triads.

Usage

simulate.RL(ideal.net, random.net, terms = "forb", k = 100, custom.terms = NULL, cr.type = "sum")

Arguments

ideal.net	ideal network structure of class matrix
random.net	random or initial network of class matrix
terms	which types of triads has to be considered (allowed allow, forbidden forb, all all or custom cust)
k	the number of iterations
custom.terms	additional terms to be considered (if terms = "cust")
cr.type	how to calculate CR value (allways use sum)

Value

new.network	generated network
change.ratio.vec	vector of CR values, each value is calculated after each iteration

Examples

##---- Should be DIRECTLY executable !! ----
##-- ==>  Define data, use random,
##--	or do  help(data=index)  for the standard data sets.

## The function is currently defined as
function (ideal.net, random.net, terms = "forb", k = 100, custom.terms = NULL,
    cr.type = "sum")
{
    teoreticna.porazdelitev <- summary(ideal.net ~ triadcensus)
    if (terms == "forb")
        allowed.terms <- names(teoreticna.porazdelitev)[teoreticna.porazdelitev ==
            0]
    if (terms == "allow")
        allowed.terms <- names(teoreticna.porazdelitev)[teoreticna.porazdelitev !=
            0]
    if (terms == "all")
        allowed.terms <- names(teoreticna.porazdelitev)
    if (terms == "cust")
        allowed.terms <- names(teoreticna.porazdelitev)[custom.terms]
    change.ratio.vec <- NULL
    new.network <- random.net
    for (i in 1:k) {
        pov <- sample(which(random.net == 0)[is.element(which(random.net ==
            0), which(diag(1, nrow = n) == 1)) == F], size = 1)
        npov <- sample(which(random.net == 1), size = 1)
        new.network[pov] <- 1
        new.network[npov] <- 0
        s.rand <- summary(random.net ~ triadcensus)
        s.new <- summary(new.network ~ triadcensus)
        if (cr.type == "mean") {
            nova.teoreticna <- mean((s.new[allowed.terms] - teoreticna.porazdelitev[allowed.terms]))
            stara.teoreticna <- mean((s.rand[allowed.terms] -
                teoreticna.porazdelitev[allowed.terms]))
        }
        if (cr.type == "sum") {
            nova.teoreticna <- sum((s.new[allowed.terms] - teoreticna.porazdelitev[allowed.terms])^2)
            stara.teoreticna <- sum((s.rand[allowed.terms] -
                teoreticna.porazdelitev[allowed.terms])^2)
        }
        change.ratio.vec[i] <- change.ratio <- nova.teoreticna/stara.teoreticna
        if (is.nan(change.ratio) == FALSE) {
            if (change.ratio < 1)
                random.net <- new.network
            else new.network <- random.net
        }
        else new.network <- random.net
    }
    return(list(new.network, change.ratio.vec))
  }

nem documentation built on April 23, 2021, 3 p.m.