cond.ranefs: Obtain conditional distribution of the random effects
In gmvjoint: Joint Models of Survival and Multivariate Longitudinal Data

cond.ranefs

R Documentation

Obtain conditional distribution of the random effects

Description

Obtain the conditional distribution of the random effects of a joint model fit. This is achieved by a Metropolis scheme. Approximate normality across random effects is expected, and could be useful in diagnosing potential issues surrounding model fits.

Usage

cond.ranefs(fit, burnin = 500L, N = 3500L, tune = 2)

Arguments

`fit`	a joint model fit by the `joint` function.
`burnin`	Number of burn-in iterations to discard, defaults to 500.
`N`	Number of MC iterations to carry out post burn-in, defaults to 3500.
`tune`	Tuning parameter, problem-specific, defaults to 2.

Value

A list of class cond.b.joint containing:

walks: A list of length n containing the history of b_i post burn-in.
acceptance: A numeric vector containing the acceptance rate for each sampled subject.
M: The ModelInfo list from joint. Used by S3 methods for class cond.b.joint.
bhats: Posterior estimates at MLEs for the random effects. Same as ranef(joint).
Sigmahats: The covariances of bhats.
D: The MLE estimate for the variance-covariance matrix of random effects from fit.
q: Dimension of random effects.
K: Number of responses.
qnames: The names of the random effects as determined by call to joint.
burnin: The amount of burn-in used.
N: Number of MC iterations.
tune: tuning parameter used
nobs: The number of observations for each subject for each response.
elapsed.time: Time taken for cond.ranefs to complete.

Examples


dat <- simData()$data
long.formulas <- list(Y.1 ~ time + cont + bin + (1 + time|id), 
                      Y.2 ~ time + cont + bin + (1 + time|id))
surv.formula <- Surv(survtime, status) ~ bin
fit <- joint(long.formulas, surv.formula, dat, list("gaussian","gaussian"))
cond.b <- cond.ranefs(fit, burnin = 50L, N = 1000, tune = 2)
cond.b
plot(cond.b) # Overall 
plot(cond.b, id = 1) # Plot the first subject (see plot.cond.b.joint).

gmvjoint documentation built on Oct. 6, 2024, 1:07 a.m.