All Questions
Tagged with nonparametric wilcoxon-mann-whitney-test
176
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P-value correction for multiple comparisons using Mann-Whitney test (using R)
I have one question regarding the adjusted p-value for multiple comparison using Mann-Whitney test.
The data structure that I am dealing with is something like this:
Two groups to compare: Group 1 vs ...
- 335
1
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1
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339
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Which form of stochastic dominance is tested for using the Mann-Whitney U hypothesis test?
The Mann–Whitney U test has the following interpretation reported on wikipedia:
[...] is a nonparametric test of the null hypothesis that, for randomly selected values X and Y from two populations, ...
- 9,411
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345
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Interpret Mann–Whitney U Test with highly skewed data
I have data for ~102,000 hands of bananas. The dataset has four data points:
Spiders present (True/False)
Count of rotten bananas in hand
Count of total bananas in hand
Percent of bananas that are ...
- 245
2
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30
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Testing tuples of response variables
I'm struggling with comparing samples with multiple response variables, where such variables have a strict precedence or importance order. For the sake of this exercise, let's assume that each sample ...
- 121
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One-sided or two-sided Wilcoxon rank-sum test depending on fold change
I am looking at fold changes $\frac{B}{A}$ over many different genes and I want to test with a Wilcoxon rank-sum test if the samples significantly differ.
I want to have as much power as possible ...
- 31
2
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2
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43
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Is there a way to quantify how appropriate a t-test is for given data?
I'm doing some programming and analysis for a post-doc who used to do this workflow using Excel and StatPlus. Apparently StatPlus has some feature where you tell it to compare two samples, and it will ...
- 241
3
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1
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298
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Step-by-step explanation of Likert scale/item statistical analysis?
I am looking for resources (books, online, articles) which have a step-by-step explanation of how to test hypothesis using Likert scale/item data. So far, I've learnt that non-parametric methods are ...
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672
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Test the hypothesis that median is zero using Wilcoxon rank sum test
A random sample of seven boys was selected from a group of boys in a senior class who lived on
farms. Another random sample of nine boys was selected from a group of boys in the same class who
lived ...
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1
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1
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Use of Mann-Whitney w/ Ties
I am tracking the results of a test between a control group and 1 variant group. Each group contains (an unequal quantity of) users whose order count we're now tracking. The histogram is heavily ...
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1
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1
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2k
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Permutation test and wilcoxon rank-sum test giving different results
I am comparing the revenue (at user level) between control & test to see if there is a significant difference. Both control & test have roughly about 39k data points . I am doing a permutation ...
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4
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1
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164
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T-Test or U-Test
I have a number of items that are based on a Likert scale, with values ranging from 1 = not at all to 5 = very much so. I would like to compare answers to these questions between two groups. I would ...
- 125
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240
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Whitney Mann U test vs Kolmogorov Smirnov for a highly skewed continuous variable
I would like to compare task time to completion distributions (measured in minutes) across two groups. The distributions are highly skewed (the means are 300 to 400 times larger than the medians) and ...
- 143
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0
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670
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Mann-Whitney U Test and Independent t-test give different results, which to use?
I have two population and I want to know if the means of the two populations are different. To the best of my knowledge, I should try an Independent t-test if the data is normality distributed and ...
- 65
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1
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724
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Mann Whitney and boostrap confidence intervals provide contradictory results
We are doing some a/b testing and have non-normal metrics so our typical t-test aren't appropriate. I typically use bootstrap CI and/or Mann whitney tests to determine the true effect. In this case ...
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Non-parametric test for station variation
Certain disease reduces the concentration of calcium in people's blood. To test the effectiveness of a drug for the treatment of the disease, 9 individuals with the disease underwent an assessment in ...
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