rms (version 5.1-2)

pphsm: Parametric Proportional Hazards form of AFT Models

Description

Translates an accelerated failure time (AFT) model fitted by psm to proportional hazards form, if the fitted model was a Weibull or exponential model (extreme value distribution with "log" link).

Usage

pphsm(fit)
# S3 method for pphsm
print(x, digits=max(options()$digits - 4, 3),
correlation=TRUE, …)
# S3 method for pphsm
vcov(object, …)

Arguments

fit

fit object created by psm

x

result of psm

digits

how many significant digits are to be used for the returned value

correlation

set to FALSE to suppress printing of correlation matrix of parameter estimates

…

ignored

object

a pphsm object

Value

a new fit object with transformed parameter estimates

See Also

psm, summary.rms, print.pphsm

Examples

# NOT RUN {
set.seed(1)
S <- Surv(runif(100))
x <- runif(100)
dd <- datadist(x); options(datadist='dd')
f <- psm(S ~ x, dist="exponential")
summary(f)        # effects on log(T) scale
f.ph <- pphsm(f)
# }
# NOT RUN {
summary(f.ph)     # effects on hazard ratio scale
# }
# NOT RUN {
options(datadist=NULL)
# }