Computes a Fisher confidence interval for a population phi correlation.
This function requires the frequency counts from a 2 x 2 contingency table
for two dichotomous variables. This measure of association is usually most
appropriate when both dichotomous variables are naturally dichotomous.
For more details, see Section 3.4 of Bonett (2021, Volume 3)
Usage
ci.phi(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 phi correlation
SE - standard error
LL - lower limit of the confidence interval
UL - upper limit of the confidence interval
References
Bishop YMM, Fienberg SE, Holland PW (1975).
Discrete Multivariate Analysis.
MIT Press.
Bonett DG (2021).
Statistical Methods for Psychologists https://dgbonett.sites.ucsc.edu/.
Examples
ci.phi(.05, 229, 28, 96, 24)
#> Estimate SE LL UL
#> 0.123 0.0548 0.015 0.229
# Should return:
# Estimate SE LL UL
# 0.123 0.0548 0.015 0.229