At the bottom of the table is the sum of the ranks for each group. Since this is not less than the critical value of U , we do not reject the null hypothesis. White and non-white citizens are not different in their satisfaction with police services. In other words, criminals and non-criminals are not different in terms of their impulsivity. The two samples come from different populations.
Criminals are more impulsive than non-criminals.
The test statistic is the Wald-Wolfowitz Runs Test. The test statistic is r which is the number of runs in the sample data. In order to determine r obt , we have to count the number of runs in the data. To find this, we first ignore the fact that we have two samples, combine the data, and assign ranks with the lowest score getting the rank of 1, and so on. Then the number of runs can be determined.