Sample size for a tetrachoric correlation confidence interval

Computes the sample size required to estimate a tetrachoric correlation with desired confidence interval precision. Set the tetrachoric planning value to the smallest absolute value within a plausible range for a conservatively large sample size.

Usage

size.ci.tetra(alpha, p1, p2, cor, w)

Arguments

alpha: alpha level for 1 - alpha confidence
p1: planning value for row 1 marginal proportion
p2: planning value for column 1 marginal proportion
cor: tetrachoric planning value
w: desired confidence interval width

Value

Returns the required sample size

References

Bonett DG, Price RM (2005). “Inferential methods for the tetrachoric correlation coefficient.” Journal of Educational and Behavioral Statistics, 30(2), 213–225. ISSN 1076-9986, doi:10.3102/10769986030002213 .

Examples

size.ci.tetra(.05, .4, .3, .5, .3)
#>  Sample size
#>          296

# Should return:
#  Sample size
#          296