Questions tagged [friedman-test]
A non-parametric test for the equality of >2 dependent groups.
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Is there a two-way Friedman's test?
I have ranked concentrations (from 0 to 5) of 5 different proteins from 3 different locations from the same patient. In total, 15 measures per patient and 61 patients, so 915 observations.
What I'd ...
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Friedman's test is very significant, but its post hoc comparisons (SPSS) are not significant
I ran a non-parametric Friedman's test for my data in SPSS 22 and significantly rejected the null. That would mean that among the $k$ paired samples (3 in my case), there should be detected at least ...
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Non-parametric test for repeated measures and post-hoc single comparisons in R?
Some attribute $x$ of 17 individuals was recorded repeatedly on 6 time points using a Likert scale with 7 distractors. Which statistical test(s) can I apply to check whether the changes along the 6 ...
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Friedman test and post-hoc test for Python
In my dataset, I have five (ordinal) groups with an x-amount of measurement. Because homoscedasticity is violated, I performed the Friedman chi-square test to see if there are any statistical ...
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All vs all post-hoc after Aligned Friedman (k classifiers over multiple datasets)
I have k classifiers and n datasets, and I have only one accuracy measurement (which is actually the average of three independent repetitions of the 5-fold-CV, i.e. average over 15 accuracy values) ...
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Post hoc test for Friedman test
I am running a Friedman test for my non-Gaussian data, on MATLAB. However, I am confused about the post hoc test to choose. Two concerns:
(1) MATLAB's multcompare ...
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Why run a post hoc wilcoxon signed rank test after Friedman test, why not just skip to Wilcoxon sign test instead?
I understand that one is required to run post hoc tests after the Friedman test. For example, while the Friedman test may find a statistically significant change amongst 3 treatments, one may follow ...
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Friedman? Unequal samples sizes
my students were involved in three different simulations. I was asked them to rate their satisfaction with these simulations on a 5-point Likert scale (several items). Unfortunately, I have 60 ...
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Repeated measurements with different measurement methods and uneven sample size - which test is suited?
I am struggling to find the appropriate statistical test to analyze my data. I hope that my question will be understandable.
I have the following setup:
A porcine spine with three vertebral bodies (...
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Multiple-Sample Cochran's Q Test
I have a data set that contains binomial samples within two conditions and several blocks, with a random, small number of samples for each condition-block combination. For example:
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Friedman's test in SPSS gives different results from R and python
I have a repeated measurement of n=452 participants. The Friedman test of SPSS gives df=2, chi-square 36.970 whereas below is the output of R and python. I cannot explain this difference for chi-...
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Friedman test for rank order question - Comparing between groups
In my study, participants ranked a total of 5 designs (different lamp types) in their order of preference (absolute favourite, second favourite, etc.). Participants ranked all lamps, and lamps were ...
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RM one-way ANOVA or Friedman test
I here my question. I'm testing with n=6 animals in 6 different situations. It's repeated measures because all 6 animals did the same tests. When I do the column statistics to see if the distribution ...
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non-parametric test: proof of Friedman's statistic
I am asked to prove that the Friedman statistic has two equivalent forms, namely:
$$
\Large
\begin{aligned}
S &= \frac{12n}{k(k+1)}\sum_{j=1}^k\left(R_{.j}-\frac{k+1}{2}\right)^2\\
&= \left[\...
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