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Computes the standard error for a point-biserial correlation

Source: R/meta_se.R
se.pbcor.Rd

Computes a point-biserial correlation and its standard error for two types of point-biserial correlations in 2-group designs using the estimated means, estimated standard deviations, and sample sizes. Equality of variances is not assumed. One type of point-biserial correlation uses an unweighted average of variances and is recommended for 2-group experimental designs. The other type of point-biserial correlation uses a weighted average of variances and is recommended for 2-group nonexperimental designs with simple random sampling (but not stratified random sampling). This function is useful in a meta-analysis of compatible point-biserial correlations where some studies used a 2-group experimental design and other studies used a 2-group nonexperimental design. The effect size estimate and standard error output from this function can be used as input in the meta.ave.cor.gen function.

For more details, see Chapter 1 of Bonett (2021, Volume 5)

Usage

se.pbcor(m1, m2, sd1, sd2, n1, n2, type)

Arguments

m1

estimated mean for group 1

m2

estimated mean for group 2

sd1

estimated standard deviation for group 1

sd2

estimated standard deviation for group 2

n1

sample size for group 1

n2

sample size for group 2

type

  • set to 1 for weighted variance average

  • set to 2 for unweighted variance average

Value

Returns a one-row matrix:

  • Estimate - estimated point-biserial correlation

  • SE - standard error

References

Bonett DG (2020). “Point-biserial correlation: Interval estimation, hypothesis testing, meta-analysis, and sample size determination.” British Journal of Mathematical and Statistical Psychology, 73(S1), 113–144. ISSN 0007-1102, doi:10.1111/bmsp.12189 .

Bonett DG (2021). Statistical Methods for Psychologists, Vol 1-5, https://dgbonett.sites.ucsc.edu/.

Examples

se.pbcor(21.9, 16.1, 3.82, 3.21, 40, 40, 1)
#>                              Estimate      SE
#> Point-biserial correlation:     0.635 0.05981

#  Should return: 
#                              Estimate      SE
#  Point-biserial correlation:    0.635 0.05981