size.ci.mean.ps: Sample size for a paired-samples mean difference confidence...

In statpsych: Statistical Methods for Psychologists

Sample size for a paired-samples mean difference confidence interval

Description

Computes the sample size required to estimate a difference in population means with desired confidence interval precision in a paired-samples design. Set the Pearson correlation planning value to the smallest value within a plausible range for a conservatively large sample size. Set the variance planning value to the largest value within a plausible range for a conservatively large sample size.

For more details, see Section 4.26 of Bonett (2021, Volume 1)

Usage

size.ci.mean.ps(alpha, var, cor, w)

Arguments

alpha	alpha level for 1-alpha confidence
var	planning value of average variance of the two measurements
cor	planning value of correlation between measurements
w	desired confidence interval width

Value

Returns the required sample size

References

\insertRef

Bonett2021statpsych

Examples

size.ci.mean.ps(.05, 5.0, .5, 2.0)

# Should return:
# Sample size
#          22
 

statpsych documentation built on Jan. 13, 2026, 1:07 a.m.