Calculate Z-residuals for a fitted survival regression model

This function calculates Z-residuals based on a fitted `survreg` object from the `survival` package.

Usage

Zresidual.survreg(fit_survreg, newdata, n.rep = 1)

Arguments

fit_survreg: A fitted object from the `survreg` function in the `survival` package.
newdata: An optional data frame containing new observations for which to calculate the Z-residuals. If `NULL` (default), residuals are calculated for the data used to fit the model.
n.rep: An integer specifying the number of random draws to use for calculating the Z-residuals for censored observations. Defaults to `nrep` (which should be defined in your environment, a common choice is 100).

Value

Survival.Prob: The estimated survival probabilities.
linear.pred: The linear predictors from the survival regression model.
covariates: The covariate values used in the model.
censored.status: The censoring status (0 for censored, 1 for event).
object.model.frame: The model frame used for the analysis.

Examples


library(survival)

# Fit a Weibull survival regression model
fit_weibull <- survreg(Surv(time, status) ~ x, data = lung, dist = "weibull")
#> Error in eval(predvars, data, env): object 'x' not found

# Calculate Z-residuals for the fitted model
z_residuals <- Zresidual.survreg(fit_weibull)
#> Error in Zresidual.survreg(fit_weibull): argument "newdata" is missing, with no default
head(z_residuals)
#> Error: object 'z_residuals' not found

# Calculate Z-residuals for new data
new_data <- data.frame(x = c(1, 2, 0.5))
Z_residuals_new <- Zresidual.survreg(fit_weibull, newdata = new_data)
#> Error: object 'fit_weibull' not found
head(z_residuals_new)
#> Error: object 'z_residuals_new' not found