homoStat {metaSEM}

Test the Homogeneity of Effect Sizes

Description

It tests the homogeneity of univariate and multivariate effect sizes.

Usage

homoStat(y, v)

Arguments

y

A vector of effect size for univariate meta-analysis or a k x p matrix of effect sizes for multivariate meta-analysis where k is the number of studies and p is the number of effect sizes.

v

A vector of the sampling variance of the effect size for univariate meta-analysis or a k x p* matrix of the sampling covariance matrix of the effect sizes for multivariate meta-analysis where p* = p(p+1)/2 . It is arranged by column major as used by vech. It is assumed that there is no missing value in v if y is complete. If there are missing values in v due to the missingness on y, the missing values in v will be removed automatically.

Value

A list of

Q

Q statistic on the null hypothesis of homogeneity of effect sizes. It has an approximate chi-square distribution under the null hypothesis.

Q.df

Degrees of freedom of the Q statistic

pval

p-value on the test of homogeneity of effect sizes

Author(s)

Mike W.-L. Cheung <[e-mail]>

References

Becker, B. J. (1992). Using results from replicated studies to estimate linear models. Journal of Educational Statistics, 17, 341-362.

Cheung, M. W.-L. (2010). Fixed-effects meta-analyses as multiple-group structural equation models. Structural Equation Modeling, 17, 481-509.

Cochran, W. G. (1954). The combination of estimates from different experiments. Biometrics, 10, 101-129.

See Also

meta

Examples

with( Hox02, homoStat(yi, vi) )

with( HedgesOlkin85, homoStat(y=cbind(d_att, d_ach),
      v=cbind(var_att, cov_att_ach, var_ach)) )