#' Point-estimates of posterior distributions #' #' Compute various point-estimates, such as the mean, the median or the MAP, to describe posterior distributions. #' #' @param centrality The point-estimates (centrality indices) to compute. Character (vector) or list with one or more of these options: \code{"median"}, \code{"mean"}, \code{"MAP"} or \code{"all"}. #' @param dispersion Logical, if \code{TRUE}, computes indices of dispersion related to the estimate(s) (\code{SD} and \code{MAD} for \code{mean} and \code{median}, respectively). #' @param ... Additional arguments to be passed to or from methods. #' @inheritParams hdi #' #' @references \href{https://easystats.github.io/bayestestR/articles/indicesEstimationComparison.html}{Vignette In-Depth 1: Comparison of Point-Estimates} #' #' @examples #' library(bayestestR) #' #' point_estimate(rnorm(1000)) #' point_estimate(rnorm(1000), centrality = "all", dispersion = TRUE) #' point_estimate(rnorm(1000), centrality = c("median", "MAP")) #' #' df <- data.frame(replicate(4, rnorm(100))) #' point_estimate(df, centrality = "all", dispersion = TRUE) #' point_estimate(df, centrality = c("median", "MAP")) #' \dontrun{ #' # rstanarm models #' # ----------------------------------------------- #' library(rstanarm) #' model <- rstanarm::stan_glm(mpg ~ wt + cyl, data = mtcars) #' point_estimate(model, centrality = "all", dispersion = TRUE) #' point_estimate(model, centrality = c("median", "MAP")) #' #' #' # emmeans estimates #' # ----------------------------------------------- #' library(emmeans) #' point_estimate(emtrends(model, ~1, "wt"), centrality = c("median", "MAP")) #' #' # brms models #' # ----------------------------------------------- #' library(brms) #' model <- brms::brm(mpg ~ wt + cyl, data = mtcars) #' point_estimate(model, centrality = "all", dispersion = TRUE) #' point_estimate(model, centrality = c("median", "MAP")) #' #' # BayesFactor objects #' # ----------------------------------------------- #' library(BayesFactor) #' bf <- ttestBF(x = rnorm(100, 1, 1)) #' point_estimate(bf, centrality = "all", dispersion = TRUE) #' point_estimate(bf, centrality = c("median", "MAP")) #' } #' #' @importFrom stats mad median sd #' @export point_estimate <- function(x, centrality = "median", dispersion = FALSE, ...) { UseMethod("point_estimate") } #' @export point_estimate.numeric <- function(x, centrality = "median", dispersion = FALSE, ...) { centrality <- match.arg(tolower(centrality), c("median", "mean", "map", "all"), several.ok = TRUE) if ("all" %in% centrality) { estimate_list <- c("median", "mean", "map") } else { estimate_list <- centrality } out <- data.frame(".temp" = 0) # Median if ("median" %in% estimate_list) { out\$Median <- stats::median(x) if (dispersion) { out\$MAD <- stats::mad(x) } } # Mean if ("mean" %in% estimate_list) { out\$Mean <- mean(x) if (dispersion) { out\$SD <- stats::sd(x) } } # MAP if ("map" %in% estimate_list) { out\$MAP <- as.numeric(map_estimate(x)) } out <- out[names(out) != ".temp"] attr(out, "data") <- x attr(out, "centrality") <- centrality class(out) <- unique(c("point_estimate", "see_point_estimate", class(out))) out } #' @export point_estimate.data.frame <- function(x, centrality = "median", dispersion = FALSE, ...) { x <- .select_nums(x) if (ncol(x) == 1) { estimates <- point_estimate(x[, 1], centrality = centrality, dispersion = dispersion, ...) } else { estimates <- sapply(x, point_estimate, centrality = centrality, dispersion = dispersion, simplify = FALSE, ...) estimates <- do.call(rbind, estimates) } out <- cbind(data.frame("Parameter" = names(x), stringsAsFactors = FALSE), estimates) rownames(out) <- NULL attr(out, "data") <- x attr(out, "centrality") <- centrality class(out) <- unique(c("point_estimate", "see_point_estimate", class(out))) out } #' @export point_estimate.emmGrid <- function(x, centrality = "median", dispersion = FALSE, ...) { if (!requireNamespace("emmeans")) { stop("Package 'emmeans' required for this function to work. Please install it by running `install.packages('emmeans')`.") } xdf <- as.data.frame(as.matrix(emmeans::as.mcmc.emmGrid(x, names = FALSE))) out <- point_estimate(xdf, centrality = centrality, dispersion = dispersion, ...) attr(out, "object_name") <- deparse(substitute(x), width.cutoff = 500) attr(out, "centrality") <- centrality class(out) <- unique(c("point_estimate", "see_point_estimate", class(out))) out } #' @importFrom insight get_parameters #' @keywords internal .point_estimate_models <- function(x, effects, component, parameters, centrality = "median", dispersion = FALSE, ...) { out <- point_estimate(insight::get_parameters(x, effects = effects, component = component, parameters = parameters), centrality = centrality, dispersion = dispersion, ...) # out\$Parameter <- .get_parameter_names(x, effects = effects, component = component, parameters = parameters) out } #' @rdname point_estimate #' @export point_estimate.stanreg <- function(x, centrality = "median", dispersion = FALSE, effects = c("fixed", "random", "all"), parameters = NULL, ...) { effects <- match.arg(effects) out <- .point_estimate_models( x = x, effects = effects, component = "conditional", parameters = parameters, centrality = centrality, dispersion = dispersion, ... ) attr(out, "object_name") <- deparse(substitute(x), width.cutoff = 500) attr(out, "centrality") <- centrality class(out) <- unique(c("point_estimate", "see_point_estimate", class(out))) out } #' @rdname point_estimate #' @export point_estimate.brmsfit <- function(x, centrality = "median", dispersion = FALSE, effects = c("fixed", "random", "all"), component = c("conditional", "zi", "zero_inflated", "all"), parameters = NULL, ...) { effects <- match.arg(effects) component <- match.arg(component) out <- .point_estimate_models( x = x, effects = effects, component = component, parameters = parameters, centrality = centrality, dispersion = dispersion, ... ) attr(out, "object_name") <- deparse(substitute(x), width.cutoff = 500) attr(out, "centrality") <- centrality class(out) <- unique(c("point_estimate", "see_point_estimate", class(out))) out } #' @rdname point_estimate #' @export point_estimate.BFBayesFactor <- function(x, centrality = "median", dispersion = FALSE, ...) { out <- point_estimate(insight::get_parameters(x), centrality = centrality, dispersion = dispersion, ...) attr(out, "object_name") <- deparse(substitute(x), width.cutoff = 500) attr(out, "centrality") <- centrality class(out) <- unique(c("point_estimate", "see_point_estimate", class(out))) out }