Rats are subjected to a drug that might cause liver damage. Suppose that for a random sample of rats, measures of liver damage are found to be
5, 12, 23, 24, 6, 58, 9, 18, 11, 66, 15, 8.
Verify that trimci returns a 0.95 confidence interval for the 20% trimmed mean, using R, equal to (7.16, 22.84). Now use trimci to get a confidence interval for the mean, resulting in (8.50, 33.99). Why is the confidence interval substantially longer?