Friedman Test Formula. The friedman test is a non parametric test for testing the difference between several related samples. A formula of the form a b c where a b and c give the data values and corresponding groups and blocks respectively.
K number of treatment groups. For any particular value of k the number of measures per subject the mean of the ranks for any particular one of the n subjects is k 1 2. Displaystyle q frac 12n k k 1 sum j 1 k left bar r cdot j frac k 1 2 right 2.
Note that the value of q does need to be adjusted for tied values in the data.
Rj2 sum of ranks for the jth group. The friedman test is an alternative for repeated measures analysis of variances which is used when the same parameter has been measured under different conditions on the same subjects. Displaystyle q frac 12n k k 1 sum j 1 k left bar r cdot j frac k 1 2 right 2. The columns contain the data of the different measurements example adapted.
