All Questions
Tagged with nonparametric wilcoxon-signed-rank
94
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Statistical test for unequal sample sizes of repeated measures (non-parametric)
I'm looking to understand the differences between various sources (50) that evaluate an event based on 8 ordinal scales (varying from 2 to 4 values) associated with a discrete score between 0 and 10, ...
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5
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1
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R removing zeros for pseudomedian and its confidence interval in wilcox.test?
It makes sense to me that we need to remove zeros to calculate the p-value in a Wilcoxon signed rank test. What confuses me is that R seems to leave the zeros deleted when computing the pseudomedian ...
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Can I use Mann-Whitney U test for within group analysis?
I am conducting a within-group study where participants rate the perceived helpfulness of ideas on a Likert scale (DV) across two different days (Day 1 and Day 2), serving as the independent variable (...
- 1,859
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4
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Business use cases for Wilcoxon signed-rank test
The Wilcoxon signed-rank test is generally used for non-parametric data (i.e. not normally distributed). When the sample gets large, the data will be approximately normally distributed. Therefore ...
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Basic question regarding before and after intervention analysis on groups of different sample size
Apologies for the basic nature of this question. I have collected data before and after an intervention and assessed response to the intervention using a survey. This was a basic survey using a 1-5 ...
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Use of Wilcoxon test for non-normal data akin to Two One Sided T-test
I'm analysing paired data for equivalency and it's not normally distributed, i.e., the difference of the paired result is not normally distributed due to, amongst other things, outliers. If it were ...
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1
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183
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What do these Wilcoxon values tell me?
I did a pre and post-test with a small number of students ($n=12$).These values came after a science intervention that took $4$ weeks. I used a Wilcoxon test for 2 related samples as there was not a ...
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28
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Non-parametric test if two samples are drawn from the same distribution
I would like to test the hypothesis that two samples are drawn from the same population, without making any assumptions about the distributions of the samples or the population. How should I do this?
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What exactly does the “symmetric distribution” assumption of the Wilcoxon signed-rank test refer to? [duplicate]
I have two lists (or sets) of data that I would like to statistically compare. More precisely, I would like to check if the difference between data list one and data list two is statistically ...
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9
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Wilcoxon Signed Rank Symmetry Assumption
The assumption of symmetricity for signed rank test (and its relevance) is becoming extremely confusing for me. I am hypothesizing that sub-population A (before treatment) and sub-population B (after ...
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What method is preferred, a bootstrapping test or a nonparametric rank-based test?
I want to perform a single-tail test on a single sample of real numbers (N~100) against an expected value. The population is known to be not normally distributed. So from what I've read about stats, I ...
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1
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How to run Wilcoxon signed-rank test for pairwise comparison of two factors with three variables each?
I performed a study where I took 9 measurements from each participant for 2 factors (time/ location) and 3 variables each. These created the following combinations:
T1L1, T1L2, T1L3, T2L1, T2L2, T2L3, ...
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1
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1
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411
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Paired sign and Wilcoxon tests with weighting
In R, I am using the survey package (inverse probability weighting) to conduct these tests on paired data:
Weighted Wilcoxon Signed Rank test
Weighted Sign test
However, I am struggling in doing ...
- 41.6k
9
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Relative efficiency of Wilcoxon signed rank in small samples
I have seen in published literature (and posted on here) that the asymptotic relative efficiency of the Wilcoxon signed rank test is at least 0.864 when compared to the t test. I have also heard that ...
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Is Wilcoxon Test appropriate for paired categorical data?
There is currently a story in the news in the UK about negative effects of puberty blockers in children: 'It showed that after a year on puberty blockers, there was a significant increase found in ...
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