A chi-square homogeneity test is to be conducted to decide whether four populations are nonhomogeneous with respect to a variable that has eight possible values. What are the degrees of freedom for the χ2-statistic?

Applying the Concepts and Skills In Exercises 13.101–13.106, use either the critical-value approach or the P-value approach to perform a chi-square homogeneity test, provided the conditions for using the test are met.