temp
| the temperature (degrees C) of the test |
time
| the time in hours to failure or censoring at 8064 hours (= 336 days). |
cens
| an indicator variable for death |
motorette
data frame has 40 rows and 3 columns. It describes an
accelerated life test at each of four temperatures of 10 motorettes,
and has rather discrete times.taken from
Nelson, W. D. and Hahn, G. J. (1972) Linear regression of a regression relationship from censored data. Part 1 simple methods and their application. Technometrics 14, 247-276.
library(survival4) data(motors) attach(motors) plot(survfit(Surv(time, cens) ~ factor(temp)), conf.int=F) # fit Weibull model motor.wei <- survreg(Surv(time, cens) ~ temp) summary(motor.wei) # and predict at 130C at130 <- predict(motor.wei, data.frame(temp=130), se.fit=T) exp(at130$fit) motor.cox <- coxph(Surv(time, cens) ~ temp) summary(motor.cox) # predict at temperature 200 plot( survfit(motor.cox, newdata=data.frame(temp=200)) )