Data from a randomised trial of two treatment regimens for lung cancer. This is a standard survival analysis data set from the classic textbook by Kalbfleisch and Prentice.
Lung object is a list containing three elements:
y:A two column matrix (
object) containing the follow-up time (in days) and an indicator
variable for whether the patient died while on the study or not.
X:Matrix of predictors
group:Vector describing how the columns of X are
X contains the following columns:
trt:Treatment indicator (1=control group, 2=treatment
polynomials of first, second, and third degree representing
Karnofsky performance score (0=bad, 100=good)
polynomials of first and second degree representing time from
diagnosis to randomization (months)
polynomials of first, second, and third degree representing the
patient's age in years
prior:Prior therapy (0=no, 1=yes)
large:Indicators for the lung cancer cell type. For
each subject, exactly one of these columns will be 1 and the rest
Kalbfleisch D and Prentice RL (1980), The Statistical Analysis of Failure Time Data. Wiley, New York.