Tidy t-test

A tidier version of t.test() for two sample tests.

t_test(
  x,
  formula,
  response = NULL,
  explanatory = NULL,
  order = NULL,
  alternative = "two_sided",
  mu = 0,
  conf_int = TRUE,
  conf_level = 0.95,
  ...
)

Arguments

x	A data frame that can be coerced into a tibble.
formula	A formula with the response variable on the left and the explanatory on the right.
response	The variable name in x that will serve as the response. This is alternative to using the formula argument.
explanatory	The variable name in x that will serve as the explanatory variable.
order	A string vector of specifying the order in which the levels of the explanatory variable should be ordered for subtraction, where order = c("first", "second") means ("first" - "second").
alternative	Character string giving the direction of the alternative hypothesis. Options are "two_sided" (default), "greater", or "less".
mu	A numeric value giving the hypothesized null mean value for a one sample test and the hypothesized difference for a two sample test.
conf_int	A logical value for whether to include the confidence interval or not. TRUE by default.
conf_level	A numeric value between 0 and 1. Default value is 0.95.
...	For passing in other arguments to t.test().

Examples

# t test for comparing mpg against automatic/manual
mtcars %>%
  dplyr::mutate(am = factor(am)) %>%
  t_test(mpg ~ am, order = c("1", "0"), alternative = "less")
#> # A tibble: 1 x 6
#>   statistic  t_df  p_value alternative lower_ci upper_ci
#>       <dbl> <dbl>    <dbl> <chr>          <dbl>    <dbl>
#> 1     -3.77  18.3 0.000687 less            -Inf    -3.91