Questions tagged [wilcoxon-signed-rank]
a non-parametric rank test to compare two paired samples, whether values in one are bigger than in the other. This test is NOT the same as the sign test.
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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 is the difference between the Wilcoxon Rank Sum Test and the Wilcoxon Signed Rank Test?
What is the difference between the Wilcoxon Rank-Sum Test and the Wilcoxon Signed-Rank Test using paired observations? I know that the Rank-Sum test allows for a different number of observations in ...
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Effect size to Wilcoxon signed rank test?
Some authors (e.g. Pallant, 2007, p. 225; see image below) suggest to calculate the effect size for a Wilcoxon signed rank test by dividing the test statistic by the square root of the number of ...
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Wilcoxon rank sum test in R
I have results from the same test applied to two independent samples:
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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 ...
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How to find out if an online poker-site is fair?
Last week I had an interesting discussion with a good friend of mine. He had been playing some online poker and suggested that there is a relationship between new subscription/additional money ...
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Repeated measures over time with small $n$
I was given data to analyze for a study looking at the effects of a treatment on iron levels at four different time points (before treatment, the day treatment ended, 4 weeks after treatment, and 2-4 ...
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Paired t-test for binary data
I have one sample with n=170 and two binary variables (A,B) that can take as a value 1 or 0, where 1 counts as a success and 0 counts as a failure. What I want to know is whether the means of these ...
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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?
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In what situation would Wilcoxon's Signed-Rank Test be preferable to either t-Test or Sign Test?
After some discussion (below), I now have a clearer picture of a focused question, so here is a revised question, though some of the comments might now seem unconnected with the original question.
It ...
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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 ...
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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:
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How to perform a Wilcoxon signed rank test for survival data in R?
Say you have survival data like this:
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How to compute the power of Wilcoxon test?
I am using Wilcoxon test to compare two paired sets of data for whether their means differ. Besides the p-value, I would also like to know the power of this test. How do I compute it in R?
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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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