McIllmurray and Turke (1987) report the ordered survival times of 21 patients with Dukes' C colorectal cancer as 3+,6,6,6,6,8,8,12,12,12+,15+,16+, 18+,18+,20, 22+,24,28+,28+,28+, and 30 months. Using these data, compute by hand the following (a) The Kaplan-Meier estimate of the survivorship function.

(b) Construct the Kaplan-Meier survival curve.

(c) Obtain a 95% confidence interval for survival at 12 months using (ii) the Greenwood variance and (ii) the log-log transformation.

(d) Estimate the hazard rate in the first year, n, and in the second year, 2