Contains the answers of 191 California high school students to the question:
"When did you first use marijuana?". An answer can be an exact age, or "I
have never used it", which gives rise to a right-censored observation, or "I
have used it but cannot recall just when the first time was", which gives
rise to a left-censored observation.
Arguments
Format
A data frame with 21 observations and 3 variables:
L: left-end point of an interval-censored time;
R: right-end point of an interval-censored time;
count: number of students in the interval.
References
Turnbull and Weiss (1978). A likelihood ratio statistic
fortesting goodness of fit with randomly censored data. Biometrics,
34, 367-375.
Klein and Moeschberger (2003). Survival Analysis: Techniques for
Censored and Truncated Data (2nd ed.). Springer