The phi-coefficient is used to evaluate effect size for a chi-square test for goodness of fit provided there are only two categories.

Question

The phi-coefficient is used to evaluate effect size for a chi-square test for goodness of fit provided there are only two categories.​

Quizplus · Accepted Answer

The phi-coefficient is used to measure the association between two binary variables, not for evaluating effect size in a chi-square test for goodness of fit. For goodness of fit, effect size might be assessed by measures like Cramer's V when dealing with categorical data in contingency tables larger than 2x2.

The Phi-Coefficient Is Used to Evaluate Effect Size for a Chi-Square