Phi and kappa

Chapter 14 Nonparametric Statistics

Phi Coefficient and Kappa Coefficient of Agreement

Agreement Among Nominally Measured Variables  Agreement between nominal variables: • Phi Coefficient • Percent Agreement • Kappa Coefficient

 The Phi coefficient is the nonparametric nominal equivalent of the parametric Pearson Product Moment Correlation Coefficient.

 Kappa adjusts percent agreement for chance agreements.

Example of Phi and Kappa  100 students tested TWICE on Fitnessgram PACER • Healthy Fitness Zone Achievement (No/Yes)

 Does HFZ achievement agree for both occasions? • Phi Coefficient • Percent Agreement • Kappa Coefficient

%Agreement = (32 + 51)/100 %Agreement = .83

SPSS Directions  AnalyzeDecriptive StatisticsCrosstab

 In the crosstabs window move PACERHFZTest1 to Row(s) and PACERHFZTest2 to Column(s). Click on Statistics.  In the Crosstabs Statistics window select 1) Phi and Cramer’s V and 2) Kappa. Click on Continue and then on OK.

Results Phi = .678 %Agreement = .83 Kappa = .653