Wilcoxon rank-sum test report results when Mdns are the same

#1
I understand that Medians should be reported when writing results of Wilcoxon rank-sum test. For example:
"For alcohol users depression levels were significantly lower on Wednesday (Mdn = 7.50) than on Sunday (Mdn = 16.0), p = .012, r = −.45."

But suppose that p=.012 but Mdn=7.50 on Wednesday and Mdn=7.50 also on Sunday, but the Mean= 6.45 on Wednesday and Mean = 14.56 on Sunday.
How do I report results? How would be the text in the example then? Because depression levels are indeed lower on Wednesday, but results should be reported using Medians..
 

obh

Active Member
#2
The Wilcoxon rank-sum compares the entire distribution (say the entire rank,).
If the two groups have a similar distribution curve, you may say that the test also compares the median
If the distribution is symmetrical median equals the average.

So you should report the results you have...
If you want you may report both the median and the average.
 
#3
But how should be the correct way to write the text for reporting results in the example? Would it be correct like this?
"For alcohol users depression levels were significantly lower on Wednesday (Mean = 6.45, Mdn=7.50) than on Sunday (Mean = 14.56, Mdn = 7.50), p = .012, r = −.45."
 

obh

Active Member
#4
Looks okay to me...maybe missing the word ranks.

I tried... to write based on slide 15 https://www.slideshare.net/plummer48/reporting-the-wilcoxon-signed-ranks-test
But it should write rank not median. (as the median is a special case only)

For alcohol users, the Wilcoxon Signed-Ranks test indicates that the ranks of the depression levels were statistically significantly higher on
Wednesday (Mean = 6.45, Mdn=7.50) than on Sunday (Mean = 14.56, Mdn = 7.50), p = .012, r = −.45."
 
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#5
Looks okay to me...maybe missing the word ranks.

I tried... to write best on slide 15 https://www.slideshare.net/plummer48/reporting-the-wilcoxon-signed-ranks-test
But it should write rank not median. (as the median is a special case only)

For alcohol users, the Wilcoxon Signed-Ranks test indicates that the ranks of the depression levels were statistically significantly higher on
Wednesday (Mean = 6.45, Mdn=7.50) than on Sunday (Mean = 14.56, Mdn = 7.50), p = .012, r = −.45."
Thanks a lot!!
 

Dason

Ambassador to the humans
#6
I would suggest reading what the Wikipedia article says about the test to better understand what it's actually telling you.

Side note: do you have data from the same people on multiple days? Or are the samples independent?
 

Karabiner

TS Contributor
#7
But how should be the correct way to write the text for reporting results in the example? Would it be correct like this?
"For alcohol users depression levels were significantly lower on Wednesday (Mean = 6.45, Mdn=7.50) than on Sunday (Mean = 14.56, Mdn = 7.50), p = .012, r = −.45."
Why didn't you perfom a dependent samples t-test, is your sample only small?

With kind regards

Karabiner