Data for Exercise 7.81

`Quality`

A data frame/tibble with 15 observations on two variables

- process
a character variable with values

`Process1`

and`Process2`

- score
results of a quality control test

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

```
boxplot(score ~ process, data = Quality, col = "lightgreen")
t.test(score ~ process, data = Quality)
#>
#> Welch Two Sample t-test
#>
#> data: score by process
#> t = -1.0106, df = 12.998, p-value = 0.3307
#> alternative hypothesis: true difference in means is not equal to 0
#> 95 percent confidence interval:
#> -1.2102969 0.4388683
#> sample estimates:
#> mean in group Process1 mean in group Process2
#> 2.514286 2.900000
#>
```