Long-tailed distributions to illustrate Kruskal Wallis test

Source: R/BSDA-package.R

Data for Exercise 10.45

Longtail

Format

A data frame/tibble with 60 observations on three variables

score

a numeric vector

group

a numeric vector with values 1, 2, and 3

ranks

ranks for variable score

References

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

Examples


boxplot(score ~ group, data = Longtail, col = heat.colors(3))

kruskal.test(score ~ factor(group), data = Longtail)
#> 
#> 	Kruskal-Wallis rank sum test
#> 
#> data:  score by factor(group)
#> Kruskal-Wallis chi-squared = 5.5622, df = 2, p-value = 0.06197
#> 
anova(lm(score ~ factor(group), data = Longtail))
#> Analysis of Variance Table
#> 
#> Response: score
#>               Df Sum Sq Mean Sq F value Pr(>F)
#> factor(group)  2  333.7  166.87  1.3917  0.257
#> Residuals     57 6834.5  119.90