All Questions
Tagged with nonparametric wilcoxon-signed-rank
23
questions
15
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3
answers
5k
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Why is the asymptotic relative efficiency of the Wilcoxon test $3/\pi$ compared to Student's t-test for normally distributed data?
It is well-known that the asymptotic relative efficiency (ARE) of the Wilcoxon signed rank test is $\frac{3}{\pi} \approx 0.955$ compared to Student's t-test, if the data are drawn from a normally ...
- 23.8k
9
votes
1
answer
5k
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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 ...
- 1,183
9
votes
5
answers
8k
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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 ...
- 93
28
votes
2
answers
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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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- 467
11
votes
2
answers
10k
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Is ordinal or interval data required for the Wilcoxon signed rank test?
Having looked at multiple online sources, I can't seem to get a straight answer. Could someone please clarify for me if ordinal data is sufficient to use for the WSRT and if not, is the sign test an ...
- 111
4
votes
2
answers
3k
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Prove the relationship between Walsh averages and Wilcoxon signed rank test
In my lecture notes it is stated that
sum of all positive signed ranks (defined in Wilcoxon signed rank test) = the number of Walsh averages that are greater than median
How can I prove this ...
- 303
11
votes
1
answer
14k
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How is the confidence interval built when executing the Wilcoxon.test in R?
I want to calculate the confidence interval around the median obtained from this data set:
...
- 283
8
votes
4
answers
6k
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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 ...
- 255
3
votes
2
answers
687
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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
2
votes
1
answer
5k
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Wilcoxon signed-rank test for proportion variable response?
My response variable is a proportion.
The explanatory variable is categorical with two levels which are not independent.
The distribution of the response variable is different from normal.
...
- 163
2
votes
1
answer
2k
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How to graph Wilcoxon test power R
I've been trying to calculate and graph the correspondent power for the wilcoxon signed test and haven't had any luck.
I tried simulating two normal distributed samples, apply the wilcoxon test and ...
- 21
12
votes
1
answer
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How to choose between sign test and Wilcoxon signed-rank test?
I am trying to pick one from these two tests to analyze paired data. Does anyone know any rules of thumb about which one to pick in general?
- 387
9
votes
1
answer
2k
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Alternative to the Wilcoxon test when the distribution isn't continuous?
One of the assumptions for using the Wilcoxon sign-rank test is that the underlying distribution is continuous (see here.)
However, there are cases (for example, when analyzing Likert scale data) ...
- 21.8k
6
votes
1
answer
3k
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What differentiates the wilcoxon test from t test regarding ordinal variables?
I'm wondering what the wilcoxon test differentiates from the t test so it can be used with ordinal variables. In other words why can't we use a t test for ordinal variables but can we use a wilcoxon ...
- 753
6
votes
1
answer
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What are the assumptions (and H0) for Wilcoxon signed-rank test?
I am working on the assumption page of the Wilcoxon signed-rank test (the wilcox "paired test") in Wikipedia.
I was able to locate a reference for the assumption that I wrote there, which are:
Let $...
- 21.8k