Data for Exercise 7.61

Rehab

Format

A data frame/tibble with 20 observations on four variables

inmate

inmate identification number

psych1

rating from first psychiatrist on the inmates rehabilative potential

psych2

rating from second psychiatrist on the inmates rehabilative potential

differ

psych1 - psych2

References

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

Examples


boxplot(Rehab$differ)

qqnorm(Rehab$differ)
qqline(Rehab$differ)

t.test(Rehab$differ)
#> 
#> 	One Sample t-test
#> 
#> data:  Rehab$differ
#> t = 0.85691, df = 19, p-value = 0.4022
#> alternative hypothesis: true mean is not equal to 0
#> 95 percent confidence interval:
#>  -0.5770068  1.3770068
#> sample estimates:
#> mean of x 
#>       0.4 
#> 
# Or
t.test(Rehab$psych1, Rehab$psych2, paired = TRUE)
#> 
#> 	Paired t-test
#> 
#> data:  Rehab$psych1 and Rehab$psych2
#> t = 0.85691, df = 19, p-value = 0.4022
#> alternative hypothesis: true difference in means is not equal to 0
#> 95 percent confidence interval:
#>  -0.5770068  1.3770068
#> sample estimates:
#> mean of the differences 
#>                     0.4 
#>