ci.tetra: Confidence interval for a tetrachoric correlation

In statpsych: Statistical Methods for Psychologists

Confidence interval for a tetrachoric correlation

Description

Computes a confidence interval for an approximation to the tetrachoric correlation. This function requires the frequency counts from a 2 x 2 contingency table for two dichotomous variables. This measure of association assumes both of the dichotomous variables are artificially dichotomous. An approximate standard error is recovered from the confidence interval.

Usage

ci.tetra(alpha, f00, f01, f10, f11)

Arguments

alpha	alpha level for 1-alpha confidence
f00	number of participants with y = 0 and x = 0
f01	number of participants with y = 0 and x = 1
f10	number of participants with y = 1 and x = 0
f11	number of participants with y = 1 and x = 1

Value

Returns a 1-row matrix. The columns are:

• Estimate - estimate of tetrachoric approximation

• SE - recovered standard error

• LL - lower limit of the confidence interval

• UL - upper limit of the confidence interval

References

\insertRef

Bonett2005statpsych

Examples

ci.tetra(.05, 46, 15, 54, 85)

# Should return:
#  Estimate         SE        LL        UL
# 0.5135167 0.09301703 0.3102345 0.6748546

statpsych documentation built on Sept. 11, 2024, 7:42 p.m.