How are the degrees of freedom for the chi-square hypothesis tests different from those of most other hypothesis tests? In most previous hypothesis tests, the degrees of freedom have been based on sample size. For the chi-square hypothesis tests, however, the degrees of freedom are based on the numbers of categories, or cells, in which participants can be counted. For example, the degrees of freedom for the chi-square test for goodness-of-fit is the number of categories minus 1: dfx2=k-1. Here, k is the symbol for the number of categories.