joineRML (version 0.4.6)

sampleData: Sample from an mjoint object

Description

Generic function used to sample a subset of data from an object of class mjoint with a specific number of subjects.

Usage

sampleData(object, size = NULL, replace = TRUE)

Value

A list of 2 data.frames: one recording the requisite longitudinal outcomes data, and the other recording the time-to-event data.

Arguments

object

an object inheriting from class mjoint for a joint model of time-to-event and multivariate longitudinal data.

size

number of subjects to include in the sampled subset. If size=NULL (default), then size is set equal to the number of subjects used to fit the mjoint model.

replace

use replacement when sampling subjects? Default is TRUE. If replacement is used, then the subjects are re-labelled from 1 to size.

Author

Graeme L. Hickey ()

Details

This function is primarily intended for internal use in the bootSE function in order to permit bootstrapping. However, it can be used for other purposes given a fitted mjoint object.

See Also

mjoint.

Examples

if (FALSE) {
# Fit a joint model with bivariate longitudinal outcomes

data(heart.valve)
hvd <- heart.valve[!is.na(heart.valve$log.grad) & !is.na(heart.valve$log.lvmi), ]

fit2 <- mjoint(
    formLongFixed = list("grad" = log.grad ~ time + sex + hs,
                         "lvmi" = log.lvmi ~ time + sex),
    formLongRandom = list("grad" = ~ 1 | num,
                          "lvmi" = ~ time | num),
    formSurv = Surv(fuyrs, status) ~ age,
    data = list(hvd, hvd),
    inits = list("gamma" = c(0.11, 1.51, 0.80)),
    timeVar = "time",
    verbose = TRUE)
sampleData(fit2, size = 10)
}