effectsize.htest get hedges g

#214

R/effectsize.R

@@ -11,7 +11,7 @@
 #' @details
 #'
 #' - For an object of class `htest`, data is extracted via [insight::get_data()], and passed to the relevant function according to:
-#'   - A **t-test** returns *Cohen's d*.
+#'   - A **t-test** depending on `type`: `"cohens_d"` (default), `"hedges_g"`.
 #'   - A **correlation test** returns *r*.
 #'   - A **Chi-squared tests of independence or goodness-of-fit**, depending on `type`: `"cramers_v"` (default), `"phi"` or `"cohens_w"`, `"oddsratio"`, or `"riskratio"`.
 #'   - A **One-way ANOVA test**, depending on `type`: `"eta"` (default), `"omega"` or `"epsilon"` -squared, `"f"`, or `"f2"`.

R/effectsize.htest.R

@@ -13,11 +13,21 @@ effectsize.htest <- function(model, type = NULL, verbose = TRUE, ...) {
         ...
       )
     } else {
-      out <- cohens_d(data$x, data$y,
-                      mu = model$null.value,
-                      paired = !grepl("Two", model$method),
-                      pooled_sd = !grepl("Welch", model$method),
-                      ...)
+      if (is.null(type)) type <- "d"
+      f <- switch(tolower(type),
+                  d = ,
+                  cohens_d = cohens_d,
+
+                  g = ,
+                  hedges_g = hedges_g
+      )
+
+
+      out <- f(data$x, data$y,
+               mu = model$null.value,
+               paired = !grepl("Two", model$method),
+               pooled_sd = !grepl("Welch", model$method),
+               ...)
     }
 
     return(out)

tests/testthat/test-effectsize.R

@@ -6,6 +6,7 @@ if (require("testthat") && require("effectsize")) {
     y <<- c(1,1:9)
     model <- t.test(x, y)
     expect_equal(effectsize(model), cohens_d(x, y, pooled_sd = FALSE), ignore_attr = TRUE)
+    expect_equal(effectsize(model, type = "g"), hedges_g(x, y, pooled_sd = FALSE), ignore_attr = TRUE)
 
     model <- t.test(x, y, paired = TRUE)
     expect_equal(effectsize(model), cohens_d(x, y, paired = TRUE), ignore_attr = TRUE)