All Questions
Tagged with nonparametric wilcoxon-signed-rank
94
questions
3
votes
2
answers
687
views
Inference of nonparametric tests as linear models
I found some statements throughout the web that suggest that most common statistical tests can be performed as general(ized) linear models (cf. here). For a Wilcoxon test the author of the referenced ...
- 159
0
votes
0
answers
2k
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Wilcoxon signed-rank test for just one sample: R vs. Python
I have tried to solve a simple college exercise about WSR test: first by hand, then in Python and finally in R. But I'm having an issue with the statistic I get.
I have a small sample of 21 numbers: 4,...
- 101
1
vote
0
answers
129
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Is 90% of the use of paired signed-rank Wilcoxon test incorrect due to violated distributional assumption of symmetry, or is it more general?
Everywhere, including forums - also this one, handbooks of statistical tests discussions, I can read that the paired Wilcoxon test does require the assumption of symmetry.
This would mean, that:
Most ...
- 11
2
votes
2
answers
530
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Mean difference analysis for a paired data with zero inflation. Can Wilcoxon test work?
I have a set of data that represent the sum of white matter streamlines termination in 64 regions of interest in the brain surface collected from 40 subjects.
Below is an example of a paired data of ...
0
votes
1
answer
95
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How to detect differences between two repeated measures for not-normally distributed variables, adjusting for a continuous covariate?
I'll explain briefly the experimental set-up.
One gruop of subject measured in two conditions:
A: with treatment (Instrumented gait analysis with foot orthosis)
B: without treatment (Barefoot ...
2
votes
0
answers
182
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Understanding a proof of the relation between Walsh averages and Wilcoxon signed rank test statistic
I am trying to understand a particular proof of the relation between Walsh averages and the Wilcoxon signed rank test statistic, as given in the book Statistical Inference Based on Ranks by T.P. ...
- 11.5k
3
votes
1
answer
1k
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Calculating statistical power for non-parametric data (using Wilcoxon signed-rank tests)
I am performing a prospective-design analysis of Patient Reported Outcome Measures from a registry of patients. I have used Shapiro-Wilk test throughout to test for normality.
All data is paired and ...
2
votes
1
answer
51
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What is the drawback of using a non-parametric test when parametric alternative could have been used? [duplicate]
I want to analyze the difference between two paired samples. My initial plan was to compare them using the Wilcoxon test because I didn't want to bother checking whether the data is properly ...
1
vote
0
answers
248
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Wilcoxon signed-rank test for count-proportions?
Let's say that I have several agents able to take action A or B, and I am interested in showing that taking action A is more likely. So I have a table that looks something like
A
B
10
2
14
6
...
.....
- 11
2
votes
1
answer
57
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Non-parametric data and comparing two treatments
I would love some help with interpreting a non-parametric test. I have data on the # of seed heads produced by an invasive plant species (n=80 plants). I applied a grazing treatment in an attempt to ...
- 21
0
votes
0
answers
311
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Wilcoxon signed rank test or t-test if data is highly skewed?
I have an variable that is highly skewed and I want to test whether my mean is equal to some fix value in another population. I only have the arithmetic mean of the other population. Because I prefer ...
- 227
3
votes
1
answer
88
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Does it make sense to run Wilcoxon rank sum test with sample size of 1 or 2?
suppose I have the following numbers.
...
- 331
1
vote
1
answer
81
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Is there any possible statistical test for this data?
I have a data set of the daily dosage of a drug that participants take against some signs and symptoms. The data are highly skewed to the left because there are a lot of patients with 0mg per day of ...
- 29
0
votes
1
answer
77
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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 ...
- 103
2
votes
0
answers
35
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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