How to get z-score from Kruskal Wallis test.

Dear

I would like to get z score (stand score) from Kruskal Wallis test.

Does MATLAB provide automatic calculation for z-score?

('z = (x – μ(mean value)) / σ(standard deviaiton)')

For example,

[p,table,stats] = kruskalwallis(data,groups);

[c,m,h,nms] = multcompare(stats,'alpha',.05,'ctype','dunn-sidak');

1 2 107.358736884486 149.713883016209 192.069029147931 0

1 3 120.836759163490 153.690374387319 186.543989611148 0

2 3 -32.2920513577527 3.97649137111020 40.2450340999731 0.991192034848183

here is the result for c, and 6th column would be p value.

For each comparison, where to get z value?

(z value for 1-2 / 1-3 and 2-3)

I really appreciate it if someone could help.

Answer 1

[Bora Eryilmaz]

The Statistics and Machine Learning Toolbox has the command to compute the zscore:

>> help zscore

zscore Standardized z score.

Z = zscore(X) returns a centered, scaled version of X, the same size as X.

For vector input X, Z is the vector of z-scores (X-MEAN(X)) ./ STD(X). For

matrix X, z-scores are computed using the mean and standard deviation

along each column of X. For higher-dimensional arrays, z-scores are

computed using the mean and standard deviation along the first

non-singleton dimension.

[Sang Hoon Kim]

Thanks~! Let me try.