Signed rank sum test 

The  Signed rank sum test is a test for symmetry about a test value. This test is the non parametric 

alternative for the One sample t test. It can be used when the observations are not Normally distributed.  

Required input  

  The variable of interest. You can use the 

 button to select variables and selection criteria.  

  The test value you want to compare the sample data with. 

Results 

The results windows for the Signed rank sum test first displays summary statistics of the sample.  

The Signed rank sum test ranks the absolute values of the differences between the sample data and the 

test value, and calculates a statistic on the number of negative and positive differences.  

If the resulting P value is small (P<0.05), then the sample data are not symmetrical about the test value 

and therefore a statistically significant difference can be accepted between the sample median and the test 

value. 

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