poseticDataAnalysis (version 1.0.0)

BuildBubleyDyerEvaluationGenerator: Generator for the approximated computation of the mean value of functions over linear extensions.

Description

BuildBubleyDyerEvaluationGenerator creates an object of S4 class BuildBubleyDyerEvaluationGenerator, for the estimation of the mean values of the input functions, over linear extensions sampled according to the Bubley-Dyer procedure. Actually, this function does not perform the computation of mean values, but just generates the object that will compute them by using function BubleyDyerEvaluation.

Usage

BuildBubleyDyerEvaluationGenerator(poset, seed, f1, ...)

Value

An object of S4-class BuildBubleyDyerEvaluationGenerator.

Arguments

poset

An object of S4 class POSet representing the poset from which linear extensions are generated. Object poset must be created by using any function contained in the package aimed at building object of S4 class POSet (e.g. POSet(), LinearPOSet(), ProductPOSet(), ...) .

seed

Positive integer to initialize random linear extension generation. Set seed=NULL for random initialization.

f1

The function whose mean value is to be computed. f1 must be an R-function having as a single parameter a linear extension of poset and returning a numerical matrix.

...

Further functions whose mean values are to be computed.

Examples

el1 <- c("a", "b", "c", "d")
el2 <- c("x", "y")
el3 <- c("h", "k")
dom <- matrix(c(
  "a", "b",
  "c", "b",
  "b", "d"
), ncol = 2, byrow = TRUE)

pos1 <- POSet(elements = el1, dom = dom)

pos2 <- LinearPOSet(elements = el2)

pos3 <- LinearPOSet(elements = el3)

pos <- ProductPOSet(pos1, pos2, pos3)

# median_distr computes the frequency distribution of median profile

elements <- POSetElements(pos)

median_distr <- function(le) {
  n <- length(elements)
  if (n %% 2 != 0) {
    res <- (elements == le[(n + 1) / 2])
  } else {
    res <- (elements == le[n / 2])
  }
  res <- as.matrix(res)
  rownames(res) <- elements
  colnames(res) <- "median_distr"
  return (as.matrix(res))
}

BDgen <- BuildBubleyDyerEvaluationGenerator(poset = pos, seed = NULL, median_distr)