All Questions
5
questions
5
votes
2
answers
178
views
Wilcoxon (WMWU) test sensitivity
Statistics courses often give the Wilcoxon-Mann-Whitney U test ("Wilcoxon" from now on) as an alternative to the two-sample t-test.
However, the test is not quite the test of medians that would be so ...
- 65k
1
vote
0
answers
871
views
How to explain to a non-statistician researcher why the 2-sample Hodges-Lehmann-estimator is reported instead of the difference in median?
I need to explain the result of the wilcox.test in R. Many people believe it's about medians. Of course it is not. I understand this is a useful non-parametric measure about statistical equality of ...
- 11
1
vote
0
answers
57
views
This is a comparison between non-normal samples of different sizes?
I have 16 types of experiments (a matrix of 4 conditions and 4 bacterial strains).
Each experiment type is composed by a variable number of samples (4-8).
Each sample is made of a variable number of ...
- 11
6
votes
3
answers
5k
views
Comparison of medians in samples with unequal variance, size and shape
What am I trying to do and how does my data look?
I am trying to perform some comparisons of medians of groups of data that, most often than not, are not-normally distributed. In some cases I am ...
- 421
16
votes
1
answer
4k
views
Why is the Mann–Whitney U test significant when the medians are equal?
I've received a results from a Mann-Whitney rank test that I don't understand.
The median of the 2 populations is identical (6.9). The uppper and lower quantiles of each population are:
6.64 & 7....
- 1,241