`R/BSDA-package.R`

`Drug.Rd`

Data for Example 7.15

`Drug`

A data frame/tibble with 28 observations on two variables

- trials
number of trials to master a task

- group
a factor with levels

`control`

and`experimental`

Kitchens, L. J. (2003) *Basic Statistics and Data Analysis*.
Pacific Grove, CA: Brooks/Cole, a division of Thomson Learning.

```
boxplot(trials ~ group, data = Drug,
main = "Example 7.15", col = c("yellow", "red"))
wilcox.test(trials ~ group, data = Drug)
#> Warning: cannot compute exact p-value with ties
#>
#> Wilcoxon rank sum test with continuity correction
#>
#> data: trials by group
#> W = 47.5, p-value = 0.02213
#> alternative hypothesis: true location shift is not equal to 0
#>
t.test(rank(trials) ~ group, data = Drug, var.equal = TRUE)
#>
#> Two Sample t-test
#>
#> data: rank(trials) by group
#> t = -2.5323, df = 26, p-value = 0.01771
#> alternative hypothesis: true difference in means is not equal to 0
#> 95 percent confidence interval:
#> -13.007341 -1.351633
#> sample estimates:
#> mean in group control mean in group experimental
#> 11.16667 18.34615
#>
```