randcov_initial {spmodel}

Create a random effects covariance parameter initial object

Description

Create a random effects (co)variance parameter initial object that specifies initial and/or known values to use while estimating random effect variances with modeling functions.

Usage

randcov_initial(..., known)

Arguments

...

Arguments to randcov_params().

known

A character vector indicating which random effect variances are to be assumed known. The value "given" is shorthand for assuming all random effect variances given to randcov_initial() are assumed known.

Details

A random effect is specified as Zu, where Z is the random effects design matrix and u is the random effect. The covariance of Zu is \sigma 2 ZZ^T, where \sigma 2 is the random effect variance, and Z^T is the transpose of Z.

Value

A list with two elements: initial and is_known. initial is a named numeric vector indicating the random effect variances with specified initial and/or known values. is_known is a named logical vector indicating whether the random effect variances in initial are known or not.

Examples

randcov_initial(group = 1)
randcov_initial(group = 1, known = "group")