Plot survival and hazard function of survreg using curve()

Question

I have the following survreg model:

Call:
survreg(formula = Surv(time = (ev.time), event = ev) ~ age, 
    data = my.data, dist = \"weib\")
             Value S         


        

Answer 1

Your parameters are:

scale=exp(Intercept+beta*x) in your example and lets say for age=40

scale=283.7

your shape parameter is the reciprocal of the scale that the model outputs

shape=1/1.15

Then the hazard is:

curve((shape/scale)*(x/scale)^(shape-1), from=0,to=12,ylab=expression(hat(h)(t)), col="darkblue",xlab="t", lwd=5)

The cumulative hazard function is:

curve((x/scale)^(shape), from=0,to=12,ylab=expression(hat(F)(t)), col="darkgreen",xlab="t", lwd=5)

The Survival function is 1-the cumulative hazard function, so:

curve(1-((x/scale)^(shape)), from=0,to=12,ylab=expression(hat(S)(t)), col="darkred",xlab="t", lwd=5, ylim=c(0,1))

Also check out the eha package, and the function hweibull and Hweibull