Practical exercise 2

a) Look at the commands given at course web-page for computing and plotting the Kaplan-Meier estimator for the lung cancer data. Perform these commands and make sure you understand the output.

b) Compute Kaplan-Meier plots separately for males and females with standard ("plain") confidence limits and use the output of the "summary" command to determine the estimates of the median survival with confidence limits for males and females.

Also estimate the lower and upper quartiles of the survival distribution for the two genders with confidence limits.

c) Repeat the calculations in b) with log-minus-log transformed ("log-log") confidence limits, and compare the results.