#' @rdname crosstable_statistics
#' @export
cramers_v <- function(tab, ...) {
UseMethod("cramers_v")
}
#' @rdname crosstable_statistics
#' @export
cramer <- cramers_v
#' @export
cramers_v.table <- function(tab, ...) {
.cramers_v(tab)
}
#' @export
cramers_v.ftable <- function(tab, ...) {
.cramers_v(tab)
}
#' @rdname crosstable_statistics
#' @export
cramers_v.formula <- function(formula, data, ci.lvl = NULL, n = 1000, method = c("dist", "quantile"), ...) {
fterms <- all.vars(formula)
tab <- table(data[[fterms[1]]], data[[fterms[2]]])
method <- match.arg(method)
if (is.null(ci.lvl) || is.na(ci.lvl)) {
.cramers_v(tab)
} else {
straps <- sjstats::bootstrap(data[fterms], n)
tables <- lapply(straps$strap, function(x) {
dat <- as.data.frame(x)
table(dat[[1]], dat[[2]])
})
cramers <- sapply(tables, .cramers_v)
ci <- boot_ci(cramers, ci.lvl = ci.lvl, method = method)
data_frame(
cramer = .cramers_v(tab),
conf.low = ci$conf.low,
conf.high = ci$conf.high
)
}
}
.cramers_v <- function(tab) {
# convert to flat table
if (!inherits(tab, "ftable")) tab <- stats::ftable(tab)
sqrt(phi(tab)^2 / min(dim(tab) - 1))
}
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.