Mann Whitney U Test

Mann Whitney U Test

1. Also called as Wilcoxon

   • Rank some test
   • Mann Whitney test
   • Two sample test

2. Is

   • Non parametric test
   • Based on ranks
   • Alternative to independent t test

3. Compares medians of 2 groups

4. Make few assumptions about data

5. Used when

   • Different variances for two groups
   • Data is
     • Not normally distributed
     • More than 5
     • Less than 20
     • Ordinal
     • Interval
     • Ratio

6. To

   • Analyze data from 2 independent groups
   • Test null hypothesis