groupedSurv (version 1.0.5.1)

betaEstFam: Estimate the Fixed Effect Parameter for the Frailty Model

Description

A method to estimate the fixed effect parameter for a frailty model accounting for family structure of related individuals (e.g., trios). The input data is assumed to be organized such that records for each family occur consecutively, and that records for offspring precede those for parents. The variance matrix for the random effects is assumed to be of the form var*K, where K is a matrix of kinship coefficients between family members. The following family structures are permitted: (Individual), (Offspring, Offspring), (Offspring, Parent), (Offspring, Parent, Parent), and (Offspring, Offspring, Parent, Parent). Other family structures have not been implemented.

Usage

betaEstFam(x, fam_group, fam_role, alpha, var, gtime, delta, lower, upper)

Value

Scalar estimate of the fixed effect parameter.

Arguments

x

Vector of numeric variables of interest for each sample.

fam_group

Vector of family IDs for each sample.

fam_role

Vector of indicators for the role within a family of each sample, i.e., {"Offspring","Mother","Father"}, or {"o","m","f"}.

alpha

Vector of baseline survival rates for each time interval.

var

Scalar for frailty variance.

gtime

Vector of observed survival times for each sample.

delta

Vector of event indicators for each sample: 1 indicates observed event, 0 indicates censored.

lower

Scalar for the lower bound of the fixed effect parameter estimation search region.

upper

Scalar for the upper bound of the fixed effect parameter estimation search region.

Examples

# Generate dummy data	
x     <- c(0, 1, 1, 1, 2, 2, 0, 0, 0)
fam_group <- c('1', '1', '1', '2', '2', '2', '3', '3', '3')
fam_role  <- c("o","f","m","o","f","m","o","f","m")
alpha <- c(0.7500000, 0.6666667, 0.5000000, 0.0000000)
var   <- 0.2
gtime <- c(1, 3, 3, 2, 1, 1, 2, 3, 1)
delta <- c(1, 0, 1, 1, 1, 0, 1, 0, 1)
lower <- 0
upper <- 2

#res   <- betaEstFam(x, fam_group, fam_role, alpha, var, gtime, delta, lower, upper) 
#res