Mann Whitney test (independent samples) 

The Mann Whitney test is the non parametric equivalent of the independent samples t test. It should be 

used when the sample data are not Normally distributed, and they cannot be transformed to a Normal 

distribution by means of a logarithmic transformation. 

Required input 

Select the variables for sample 1 and sample 2.  Use the 

  button to select variables and selection 

criteria in the variables list.   

Results 

The  Mann Whitney test combines an  

d ranks the data from sample 1 and sample 2 and calculates a 

statistic on the difference between the sum of the ranks of sample 1 and sample 2.  

If the resulting P value is small (P<0.05) then a statistically significant difference between the two sample 

medians can be accepted. 

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