All Questions
Tagged with nonparametric wilcoxon-mann-whitney-test
176
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Using an old trained model on a new data - comparing two populations
I have two populations with the same set of features. The range of the features' values is also the same.
I trained Random Forest Algorithm on the first population. Thus, I wonder whether or not I can ...
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Confused about the Mann-Whitney $U$ test. Does it test distribution equality (pdf) or just mean/median equality?
I am rather confused about the Mann Whitney test, many statements I read state it tests for distribution equality between two populations and some state it tests for means/median/central tendency only....
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Are there standards for reporting non-parametric test results?
pretty basic question here. I'm pretty sure similar questions have been asked before (if you have any references that may help, you can send them too). Thanks in advance!
I conducted some Wilcoxon ...
- 81
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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
2
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1
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Which statistical analysis should I perform if the data sets are not normally distributed?
I am doing an experiment where there are two independent groups; one is the group of "infected" patients another is the group of "sepsis" patients. I am comparing "platelet monocyte aggregates(PMA)" ...
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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 ...
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6
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3
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Mann Whitney Test: Clearing Up Confusion
I have been reading many statistical websites stating that the Mann Whitney test is a test of medians. However, I believe that this is not really true? It is a test of the difference in the ranks. The ...
- 162
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One-sample versions of the signed rank and rank sum tests?
I wonder if there are applications of the signed rank and rank sum tests in a one-sample context?
Signed rank
Is there a form of the signed rank test where the difference $A-B$ for each subject is ...
- 30.3k
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Can I use the Mann-Whitney U test sequentially (pairwise) when I have three groups or do I need to use the Kruskal-Wallis test?
My question has three parts (the method and results for my experiment follow the questions):
If I have three groups of non-parametric sample data, can I use the Mann-Whitney U test to test the Null ...
- 213
1
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722
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How to find the difference between two set of scores of a single participant?
What I am trying to do?
I have a data set which consists of only one undergraduate student's all courses scores. Let's assume, he has completed about 70 courses where 40 courses are related to ...
- 294
3
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1
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398
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Mann Whitney U revenue test effect size
I am looking for solutions around non-parametric hypothesis testing on revenue metrics in business settings.
Currently I face with difficulties in finding the right way to make a Mann-Whitney U test ...
- 201
3
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1
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Which test(s) are alternative to Mann-Whitney test for non-parametric continues data when symmetry assumption is violated
From here and here I see that we cannot use Mann-Whitney test if symmetry assumption is violated. Which test(s) can we use instead of Mann-Whitney test for non-parametric continues data if symmetry ...
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1
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1
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216
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Variance in a T-test using means/medians
I have turning data for animals in different conditions with comparisons of before and after these conditions, we'll say condA condB.
Each animal has 3 repeats on both conditions, where before a ...
- 127
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584
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What is exactly the non-normality requisite for nonparametric tests? [duplicate]
As the title says, what is exactly what is being tested before deciding to use a non-parametric alternative test (as Kruskal-Wallis for ANOVA, or Mann-Whitney's U for student's t)?
Most sources are ...
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3
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446
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Multiple comparisons between two groups (non-parametric)
Update Added more details about the Experimental setup.
My experiment comprised two groups, control (N=25) and experimental (N=26). Each participant belonged to one group. Their performance has been ...
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