How we change what others think, feel, believe and do

 Disciplines Techniques Principles Explanations Theories
 Home Blog! Quotes Guest articles Analysis Books Help us Links

# Phi (f) Correlation

Explanations > Social ResearchAnalysis > Phi (f) Correlation

## Description

Phi (f) correlation is used to assess correlation between two variables where they are in a 2 x 2 table (ie. both variables are dichotomous).

Phi is calculated by first calculating chi-square, then using the following calculation:

f = SQRT(c2 / N)

## Discussion

Chi-square says that there is a significant relationship between variables, but it does not say just how significant and important this is. Phi correlation is a post-test to give this additional information.

Phi varies between -1 and 1. Close to 0 it shows little association between variables. Close to 1, it indicates a strong positive association. Close to -1 it shows a strong negative correlation.

Remember that Phi is only of use in 2x2 tables. Where tables are larger, use Cramer's V.

 More Kindle books:

And the big
paperback book

### Theories

Massive Content -- Maximum Speed