First Kaplan-Meier estimate
In this exercise, we will use the same data shown in the video. We will take a look at the survfit() function and the object it generates. This exercise will help you explore the survfit object.
The survival package is loaded for you in this exercise.
Questo esercizio fa parte del corso
Survival Analysis in R
Istruzioni dell'esercizio
- Explore the use of the
survfit()function by entering?survfitin the console. - Compute the Kaplan-Meier estimate using
survfit(). - Take a look at the structure of the
survfitobject usingstr(). - Create a
data.framewith the four time points, the corresponding number at risk (n.risk), number of observations with an event (n.event), number of observations censored (n.censor) and the value of the survival curve (surv). Take all info from thesurvfitobject.
Esercizio pratico interattivo
Prova a risolvere questo esercizio completando il codice di esempio.
# Create time and event data
time <- c(5, 6, 2, 4, 4)
event <- c(1, 0, 0, 1, 1)
# Compute Kaplan-Meier estimate
km <- survfit(___(___, ___) ~ ___)
km
# Take a look at the structure
str(___)
# Create data.frame
data.frame(time = km$time, n.risk = ____, n.event = ____,
n.censor = ____, surv = ___)