extract_t_test(x, y, ...)

Run a Welch t-test and return a tidy data frame with means, SDs, t-statistic, p-value and significance stars.

statistics

Args:x — first numeric vectory — second numeric vector

extract_t_test <- function(x, y, ...) {
  z <- t.test(x, y)
  stat <- z$statistic
  pval <- z$p.value
  pvalStars <- ifelse(pval > 0.05, ".",
                      ifelse(pval > 0.01, "*",
                             ifelse(pval > 0.001, "**", "***")))
  est <- z$estimate
  sdv <- c(sd(x), sd(y))

  res <- data.frame(est[1], sdv[1], est[2], sdv[2], stat, pval, pvalStars)
  res[1:4] <- round(as.numeric(res[1:4]), 2)
  names(res) <- c("Mean x", "sd x", "Mean y", "sd y", "t", "Pvalues", "P")
  return(res)
}