size.ci.phi {statpsych}R Documentation

Sample size for phi correlation confidence interval

Description

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

Usage

size.ci.phi(alpha, p1, p2, phi, 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

phi

planning value for phi correlation

w

desired confidence interval width

Value

Returns the required sample size

Examples

size.ci.phi(.05, .7, .8, .35, .2)

# Should return:
#  Sample size
#          416



[Package statpsych version 1.8.0 Index]