good way to judge the effect of an outlier is to do your analysis twice, once with the outlier and a second time without it. The data in Exercise 18.32 follow a Normal distribution quite closely except for one patient with HAV angle 50 degrees, a high outlier.
(a) Find the 95% confidence interval for the population mean based on the 37 patients who remain after you drop the outlier.
(b) What is the most important effect of removing the outlier?