se.stdmean.ps {vcmeta}

Computes the standard error for a paired-samples standardized mean difference

Description

This function computes the standard error of a paired-samples standardized mean difference using the sample size and estimated means, standard deviations, and estimated correlation. The effect size estimate and standard error output from this function can be used as input in the meta.ave.gen, meta.lc.gen, and meta.lm.gen functions in applications where compatible standardized mean differences from a combination of 2-group and paired-samples experiments are used in the meta-analysis. Equality of variances is not assumed.

Usage

se.stdmean.ps(m1, m2, sd1, sd2, cor, n, stdzr)

Arguments

m1

estimated mean for measurement 1

m2

estimated mean for measurement 2

sd1

estimated standard deviation for measurement 1

sd2

estimated standard deviation for measurement 2

cor

estimated correlation for measurements 1 and 2

n

sample size

stdzr

• set to 0 for square root average variance standardizer

• set to 1 for measurement 1 SD standardizer

• set to 2 for measurement 2 SD standardizer

Value

Returns a one-row matrix:

• Estimate - estimated standardized mean difference

• SE - standard error

References

Bonett DG (2009). “Meta-analytic interval estimation for standardized and unstandardized mean differences.” Psychological Methods, 14(3), 225–238. ISSN 1939-1463, doi:10.1037/a0016619.

Examples

se.stdmean.ps(23.9, 25.1, 1.76, 2.01, .78, 25, 0)

# Should return: 
#                                   Estimate        SE
# Standardizedd mean difference:  -0.6352097 0.1602852