R/guess_lik.R

In soodoku/guess: Adjust Estimates of Learning for Guessing

#' guess_lik
#' @description Likelihood function for data without Don't Know. Used Internally.
#' @keywords internal
#' 
#' @param x    lgg, lgk, lkk
#' @param g1   guess
#' @param data transition matrix

guess_lik <- function(x, g1 = x[4], data) {

  lgg <- x[1]
  lgk <- x[2]
  lkk <- x[3]

  vec <- NA
  vec[1] <- (1 - g1) * (1 - g1) * lgg
  vec[2] <- (1 - g1) * g1 * lgg + (1 - g1) * lgk
  vec[3] <- (1 - g1) * g1 * lgg
  vec[4] <- g1 * g1 * lgg + g1 * lgk + lkk

  -sum(data * log(vec))
}