Sample size for a between-subjects mean linear contrast confidence interval
Source:R/statpsych1.R
size.ci.lc.mean.bs.Rd
Computes the sample size in each group (assuming equal sample sizes) required to estimate a linear contrast of population means with desired confidence interval precision in a between-subjects design. Set the variance planning value to the largest value within a plausible range for a conservatively large sample size.
Examples
v <- c(.5, .5, -1)
size.ci.lc.mean.bs(.05, 5.62, 2.0, v)
#> Sample size per group
#> 34
# Should return:
# Sample size per group
# 34