var_pop: var_pop

In RobbievanAert/puniform: Meta-Analysis Methods Correcting for Publication Bias

var_pop

Description

Function for estimating the population variance of correlated outcomes' effect size within a primary study.

Usage

var_pop(v, r)

Arguments

v	A numerical value specifying the sampling variance of the effect size (see Details)
r	A numerical value specifying the Pearson correlation coefficient between the outcomes (see Details)

Details

This function estimates the population variance of the effect size of correlated outcomes within a study. That is, it estimates the population variance from a single draw of a multivariate normal distribution. The function assumes equal true effect size of all outcomes, equal sampling variances of the outcomes' effect size, and equal correlation (i.e., r) among the outcomes.

For a derivation of this estimator see van Aert & Wicherts (2023).

The variance that is computed with this function can be used to correct for outcome reporting bias by including the variance as a moderator in a (multivariate) meta-analysis. Please see van Aert & Wicherts (2023) for more information.

Value

The var_pop function returns a numerical value that is the estimate of the population variance of correlated outcomes' effect size given v and r.

Author(s)

Robbie C.M. van Aert [e-mail]

References

van Aert, R.C.M. & Wicherts, J.M. (2023). Correcting for outcome reporting bias in a meta-analysis: A meta-regression approach. Behavior Research Methods.

Examples

### Compute variance for an artificial example
var_pop(v = 0.1, r = 0.3)

RobbievanAert/puniform documentation built on Sept. 22, 2023, 2:53 a.m.