In the article “Caudal analgesia in paediatrics: a comparison between bupivacaine and ketamine” published in The Internet Journal of Anesthesiology (Siddiqui and Choudhury, 2006), the authors reported the results of a study on the mean time intervals between the recovery from anesthesia and the first dose of analgesia for three treatments. Each of the three treatments was replicated 20 times. Table 12.33 contains the summary statistics that were reported in the article, and the ANOV table given in Table 12.34 was reconstructed from the information in Table 12.33.

Use Tables 12.33 and 12.34 to answer the following:

(a) On the basis of the information in Table 12.33, is it reasonable to assume the treatment groups have a common variance? Explain.

(b) Test the hypothesis of the equality of the treatment means at the ???? = 0.05 level.

(c) Determine the Bonferroni distance ???? for separating the treatment means when the experimentwise error rate is ????E = 0.05.

(d) Separate the treatment means and summarize the separation of the treatment means using the underlined notation.

(e) Compute a 95% confidence interval for the difference between the means of the bupivaciane treatment and the ketamine treatment.

(f) Compute a 95% confidence interval for the mean of the ketamine treatment.