Questions tagged [friedman-test]
A non-parametric test for the equality of >2 dependent groups.
138 questions
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Help with choosing the correct statistical method
I have a dataset with measured concentration of DNA for blood drops on paper for 8 donors. From these paper blood drops, little punches are made (1, 2, or 3 for each donor). The punches are made from ...
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Alternative to Friedman test when data has missing participants
I have a dataset (three groups and multiple participants responding to multiple variables) that violates the assumptions of normality and independence. I am running Friedman test in R to identify the ...
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Quantifying uncertainty after Friedman test with low sample size
We are testing a water filtration machine that filters lake water using two sequential filters. The goal is to determine whether the machine effectively removes certain chemicals.
To test this, we ...
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Reject H0 on Friedman test but fail to reject in any pairwise wilcoxin test
I am currently working compare auroc of different models, and I did Friedman test first and then Pairwise Wilcoxon test to see difference.
The test data: data link
The data was generated with SVM, ...
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SPSS: related-samples friedman's two-way analysis of variance by ranks extra bar in graph [closed]
I'm new here, and somewhat of a lay-user in terms of statistics, and hoping this question will be at the appropriate place.
I'm running the mentioned analysis in SPSS on 3 iterations of an experiment ...
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Maximum value of Friedman's randomized block statistic
I'm reading about Friedman's statistic from the 3rd edition of Nonparametric Statistical Methods (Hollander, Wolfe and Chicken). On page 302 they have an exercise problem:
Show directly, or ...
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What’s the appropriate statistical test to compare ML model performance over CV folds?
I’m comparing the performance of 10 ML models across 15-fold cross-validation, using metrics like MSE. Each model’s performance is ranked per fold, and I want to determine if there are significant ...
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Issue with Friedman test in GraphPad Prism
I am analyzing the GC-rich to AT-rich cell-free DNA fragment number ratio in the whole genome context and different genomic (gene, repeat, etc.), epigenomic (heterochromatin, euchromatin), and ...
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Using Friedman Test for Time-of-Day Analysis on Vaccine Fridge Data?
I worked on a project monitoring vaccine fridge temperatures, collecting data every 30 seconds over two years. I want to compare high temperature anomalies (above 8°C) across different times of the ...
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Strange issue with Friedman pairwise post-hoc evaluation vs Wilcoxon test
I have a dataset with 15 patient samples in the medical field. The data seems to be non-normal distributed. I am planning to compare the 5 different paired measurement levels (T1 to T5) of a biomarker....
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Can a Friedman's ANOVA be used for groups of different size?
The independent variable in my data is verb class: I have got four verb classes, each consisting of ten verbs. The dependent variables are accuracy (either 0 - incorrect or 1 - correct), and reaction ...
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What Statistical test to use on my project?
I am very confused about what kind of statistical test to use in RStudio on my project,
I have measured the mean salinity for 3 levels of population density (low medium and high) across 6 months (...
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How should I analyze data that is paired and also repeatedly measured?
I have data collected from the same subjects (n=10) over 11 days, with measurements taken under two conditions each day: immediately after training(D0) and 30 minutes after training(D30). The data is ...
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Alternative to Nemenyi posthoc test that can use variance
I am applying statistical tests from paper "Statistical Comparisons of Classifiers over Multiple Data Sets" J. Demsar (link) in my own work. However, variance is pretty important, since ...
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Is there any post-hoc test for multiple comparisons after conducting the Friedman test by two group using a preference ranking questionnaires?
I have this dataframe:
group1<- matrix(c(rep(1,5),rep(2,5),rep(3,5),rep(4,5)), ncol=4)
group2<- matrix(c(rep(4,5),rep(3,5),rep(2,5),rep(1,5)), ncol=4)
I ...
Javi
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Why is my Friedman posthoc test said to be "true" with a p value of 0.06?
I used the function friedman.test to test for differences between multiple conditions and then used friedmanmc as a posthoc test....
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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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Why is my result significant when there is no difference between means?
I have run a Friedman's test in R and it has given me the following result:
...
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Alternative to Friedman Test in R
I am trying to run a Friedman Test in R with a repeated measure, however, my data do not qualify as an unreplicated complete block design. I am wondering what ...
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Error when conducting a Friedman Test in R
I am trying to run a Friedman Test on some data in R. I would like to measure a 3-way interaction with a repeated measure. However, I keep getting a persistent error message when I run the code and ...
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Hypothesis Test for Ranked Preference?
I am conducting a survey where people are required to rank 3 different designs from 1st to 3rd. For example, there are 3 designs - A, B and C. Participants are required to rank them in order of ...
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Calculate CI for chi-squared of the Friedman test in R
I have a dataset (not normal distribution) with repeated measures over time. As such I was planning to use the Friedman.test in R:
friedman.test(dash ~ time | nr)
...
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Clustered data and the Friedman test
Good morning, I am performing a risk factor analysis of the individual and household-level factors associated with Plasmodium infection in individuals located in 8 villages in Cambodia.
I have ...
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Post-hoc tests after Friedman test
In Statistical Comparisons of Classifiers over Multiple Data Sets (p. 12) Janez Demsar suggests to use the Bonferroni-Dunn test as a post-hoc test after the null hypothesis of an initial Friedman test ...
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Trouble interpreting Friedman Test for 3-way repeated measures ANOVA
I would like to use a Friedman Test as a non-parametric alternative to a 3-way ANOVA in RStudio. I would like to measure how 'cl_conc' (Response Variable) is affected by 'soil_type' (Fixed Effect #1 - ...
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Friedman test_multiplicity
I'm performing Friedman test to see if there is a difference between 8 treatments, then if it is significant I'll do Wilcoxon signed rank test to see which pair is significant. I wonder if I should ...
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Repeated Measures, or just measuring the same thing, repeatedly?
I understand what "repeated measures" denotes - given a set of subjects, if each subject receives more than one treatment, we call this repeated measures, or "within subjects." But ...
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Analyse ordinal data between subjects
I have two groups of participants, group 1 looked at four images under condition 1, and group 2 looked at the four images under condition 2. I want to see whether the condition influenced the order in ...
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Friedman's test and unequal sample sizes
I have movement information from 4 animals across different moon phases. I want to compare if their movement (eg. distance traveled per night) varied among different moon phases. However, I do not ...
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How does the Friedman test extend the sign test?
Every book/article claims this as if it's self-evident, but I have a hard time figuring out why. How do you get from the sum-of-squares style statistic of Friedman to the difference statistic involved ...
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Kruskal-Wallis versus Friedman - Paired data, but not repeated measures/blocks?
I'm trying to compare the difference in behaviour of an animal with no enrichment to the same animal with two (or more) types of enrichment. (Total active behaviours before/total active behaviours ...
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Friedman Test not working. Is this the appropriate statistical test?
I am trying to determine if the mean distance between animal pairs changes across months. According to a Shapiro Wilk test, my mean distance measurements are not normally distributed. Due to this, I ...
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Compare mean of subsamples between groups
I am going to collect quantitative data for two groups that I would like to compare. I have done a two sample t-test on some preliminary data and found a significant difference, but I don't think that ...
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Effect size measure for post-hoc tests after nonparametric tests: Alternatives to calculating r from z score?
I've calculated Friedman's tests for my data and want to report an effect size with the individual post-hoc tests that followed on from the statistically significant Friedman's test.
I use the formula ...
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Which ANOVA / non-parametric alternative should I use?
Apologies if this is a really simple question but I cannot work it out.
I am trying to find out if year and/or location influence the amount of insects caught. Insects are measured in grams per 10km2. ...
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Which statistical method can be used to compare the values of the same variables measured from different views?
I got a biological data set, where I need to run a statistical analysis on.
The data was created on a mass spectrometer and contains the intensity values for around one hundred lipids.
The analysis ...
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Compute Exact Null Distribution for Friedman Statistic
Problem Statement: If there are no ties and $b=2,\;k=3,$ derive the exact null distribution of $F_r,$ the Friedman statistic.
Note: This is Exercise 15.35 in Mathematical Statistics with Applications, ...
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What test to perform on my complicated data...?
I have data that looks like this:
I'm trying to analyze time and num_collisions. Subjects completed each combination of device/rho/lam/hmd x 6 trials [within subjects design, repeated trials]
There ...
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Not sure what test to run to compare the proportions of a count outcome across a variable with 5 levels, between two groups (using R for analyses)
For a case-control study that I've conducted I've measured how many times a count outcome (count_outcome) occurred in each of 4 areas (...
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An a posteriori test to determine non difference across >3 groups given a skewed continuous variable of interest, as an alternative to a Friedman-test
Given a set of items of which each item is once measured using a computative model, each time under a different condition, what is the best way to quantify the magnitude of difference between ...
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How can we prove that kruskal wallis test and jonckheere test is equivalent to wilcoxon rank sum test?
How can we prove that kruskal-Wallis test and Jonckheere test is equivalent to Wilcoxon rank sum test when k = 2?
And how can we prove that Friedman test and Page test is equivalent to sign test when ...
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Finding out the best experimentalist based on statistical analysis
There are $m$ students in a laboratory. Each student is assigned the same task, which is described below.
i). $n$ unknown standards are given to each of them.
ii). Each standard has to be analyzed $p$ ...
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Friedman's test is very significant, but its post hoc comparisons are not significant
This post does not include an answer for my question.
I have perform a Friedman test on a results obtained by several methods on multiple datasets, as described in this paper: "Statistical ...
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Should I rank my data before doing post hoc Dunn test?
I am trying to compare multiple algorithms using the Friedman test and post hoc Dunn test. I know that we should use the rank of our data before performing the Friedman test, but should we rank the ...
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Should I use Friedman test or Mixed Model for my data in R? Nested or not?
I have my Response variable which is Proportion of Range Exposed to extreme events for terrestrial mammal species in the future. More clearly, it is the Difference of Proportion of Range Exposed (DPRE)...
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Every time I run a statistical test, my n-value is doubled
I just finished collecting data for a small study with a within-subject design looking at caching behaviour and how it can be affected by a bird's surroundings. My study had three experimental ...
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Statistical significance test for 5-fold cross validation on a single dataset
I have used stratified 5-fold cross validation to generate five data folds to compare several (N) deep learning models on a single dataset. Now, I have the fold-wise test accuracies for all of the ...
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Kruskal-Wallis test for ranking data
I have a complex experimental design where there are 3 groups, and in each group, a ranking/comparison is made between items (list of items). Each ranking is associated with 9 measurements on a 5 ...
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Error in friedman.test.default(c(3.7005, 1.3212, 2.0572, 1.8833, 0.4539, : not an unreplicated complete block design [closed]
I have a non-parametric data and would like to run Friedman Test.
Here is my code:
res <- data_copy %>% friedman_test( ten ~ res | order)
res
However, I got ...
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Computing statistical Significance of Rank Order Question
In my questionnaire, I have a rank order question concerning three different videos. Each respondent must rank each of the videos either on position 1, 2 or 3. All respondents are in the same group (...
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