metaSEM: rCor – R documentation

Become an expert in R — Interactive courses, Cheat Sheets, certificates and more!

rCor

Generate Sample/Population Correlation/Covariance Matrices

Description

It generates random sample or population correlation or covariance matrices. rCor() is a wrapper to call rCorPop() and then rCorSam().

Usage

rCor(Sigma, V, n, corr=TRUE, raw.data=FALSE,
     nonPD.pop=c("replace", "nearPD", "accept"),
     nonPD.sam=c("stop", "nearPD"))
rCorPop(Sigma, V, k, corr=TRUE, 
        nonPD.pop=c("replace", "nearPD", "accept"))
rCorSam(Sigma, n, corr=TRUE, raw.data=FALSE, 
        nonPD.sam=c("stop", "nearPD"))

Arguments

`Sigma`	A list of population correlation/covariance matrices or a single matrix
`V`	A variance-covariance matrix of Sigma.
`n`	A vector or a single sample sizes.
`corr`	Logical. Whether to generate correlation or covariance matrices.
`raw.data`	Logical. Whether correlation/covariance matrices are generated via raw.data or directly from a Wishart distribution.
`nonPD.pop`	If it is `replace`, generated non-positive definite matrices are replaced by generated new ones which are positive definite. If it is `nearPD`, they are replaced by nearly positive definite matrices by calling `Matrix::nearPD()`. If it is `accept`, they are accepted.
`nonPD.sam`	If it is `stop`, the program stops when the inputs in the `rCorSam` are non-positive definite. If it is `nearPD`, they are replaced by nearly positive definite matrices by calling `Matrix::nearPD()`.
`k`	A vector or a single number of studies.

Value

An object of the generated population/sample correlation/covariance matrices.

Author(s)

Mike W.-L. Cheung <mikewlcheung@nus.edu.sg>

Examples

Sigma <- matrix(c(1, .2, .3,
                  .2, 1, .4,
                  .3, .4, 1), ncol=3, nrow=3)
V <- diag(c(.1, .1, .1))

## Generate two population correlation matrices
Pop.corr <- rCorPop(Sigma, V, k=2)
Pop.corr
                  
summary(Pop.corr)
                  
## Generate two sample correlation matrices
rCorSam(Sigma=Pop.corr, n=c(10, 10))
                 
## The above code is the same as the following one
rCor(Sigma, V, n=c(10, 10))

metaSEM

Meta-Analysis using Structural Equation Modeling

v1.2.5

GPL (>= 2)

Authors

Mike Cheung [aut, cre] (<https://orcid.org/0000-0003-0113-0758>)

Initial release

2020-11-29