R/statpsych1.R
size.ci.stdmean.ps.Rd
Computes the sample size required to estimate two types of population standardized mean differences (unweighted standardizer and single group standardizer) with desired confidence interval precision in a paired-samples design. For a conservatively large sample size, set the standardized mean difference planning value to the largest value within a plausible range and set the Pearson correlation planning value to the smallest value within a plausible range.
size.ci.stdmean.ps(alpha, d, cor, w)
alpha level for 1-alpha confidence
planning value of standardized mean difference
planning value of correlation between measurements
desired confidence interval width
Returns the required sample size for each standardizer
Bonett DG (2009). “Estimating standardized linear contrasts of means with desired precision.” Psychological Methods, 14(1), 1--5. ISSN 1939-1463, doi:10.1037/a0014270 . 0
size.ci.stdmean.ps(.05, 1, .65, .6)
#> Sample size
#> Unweighted standardizer: 46
#> Single group standardizer: 52
# Should return:
# Sample Size
# Unweighted standardizer: 46
# Single group standardizer: 52