The times in minutes required for students at a West Coast university to get ready in the morning are 60 12 35 30+ 5 20 where the + denotes a right-censored time for a student who reported that he took at least 30 minutes.
a. Construct the Kaplan-Meier estimator for S(t) using the observed times to get ready. Sketch a graph of the curve.
b. Using your answer to Part A, estimate the proportion of university students who take longer than 30 minutes to get ready.
c. Estimate the mean time to get ready in the morning using an appropriate expression.