interpreting wilcoxon output confusion

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interpreting wilcoxon output confusion

Leila Durr
this might sound like a totally basic question- and for that i apologize-
but i'm really struggling to understand how to interpret the SPSS output
of the wilcoxon signed rank test (for 2 related samples).  i'm trying to
understand what a negative of positive Z score value means (if anything).
i'm also trying to figure out interpretation beyond is there significance--
 but which one is significant (especially when i'm running the test one-
tailed).  i hope that made sense.. it's hard to explain when i'm
confused!! thanks.
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Re: interpreting wilcoxon output confusion

jpmaroco
Hi Leila,
Look at your mean ranks when doing one tailed tests.
If MeanRank1 < MeanRank2 the one-sided p-value is for the left-onesided test. Otherwise if for the Right sided.
The Z statistics numerator is (Min (W1, W2)- E(W)) and thus is always negative (if I am seeing it right). Cannot use that to decide if the one-sided test is left or right sided.
Best
João