Questions tagged [friedman-test]
A non-parametric test for the equality of >2 dependent groups.
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Friedman test for small sample single arm trial?
I am looking at a single arm clinical study with a small sample size (n=14), where each patient was assessed 5 times (weeks 1-5, once a week). I have constructed linear models to see if the change-...
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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 ...
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What is the most common Nonparametric Global Test of Difference for Repeated Measure?
The experiment goes like, there are two different machines, Machine_A and Machine_B and a Technician. The machines have the same purpose which is for measuring a continuous quantity (be it weight, ...
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Is there a method bias when I prefer a specific post-hoc that shows a significance after significance in test of difference in groups?
I'm working to see if a machine does better than a worker in terms measurement (by having a measurement from an expert be the control). So my dataframe contains the Measurement Value, Measuring Device,...
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Which test in this case ? Friedman not possible
I have done a benchmarking of multiple learners on multiple tasks with nested CV (inner loop : CV 3F, and outer loop : CV 3F). My datas have 1052 observations and each task have 10-12 features.
I ...
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What is an appropriate post hoc test after the Friedman test?
I've read several posts related to this, but I'm not sure.
so I'm posting the question in case it's redundant.
I have been conducting an experiment using a within-subject design, comparing three ...
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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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What is the best recommendation for analyzing 4 data sets, each with 10 observations at 10 times?
Four samples were analyzed daily for 5 days. It is known that time influences the values of the analyses, because the samples are sensitive to the passage of time. Here is a table illustrating the ...
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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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Analysing multiple categorical variables at different time points for several dependent variables in R?
For my master's thesis I've gotten pretty stuck with the analyses. I have 5 categorical treatments (predator model presentations) and I've measured how birds respond to them at 3 different time points ...
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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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Friedman on one subject?
my goal is to define the interaction between 2 compounds. The data did not meet the assumptions of Two way Anova. I understand their is no alternative to testing the interaction. I am less interested ...
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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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Reps parameter in matlab's friedman function
Say I was comparing 3 columns, each a different level of an independent variable I'm investigating. I collected data on 6 (A-F) subjects, on each of whom I took 4 (1-4) independent measurements for ...
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Check for interaction of two categorical independent variables within subject design and non normal continuous dependent variable
we have conducted a study with two categorical independent variables with 3 and 4 levels respectively. We used a within-subject design and have a non-normal continuous dependent variable. I did a ...
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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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What Statistical test should I use
I am conducting an empirical study, I applied 3 treatments on the sample of 23 objects. The treatments 1 and 2 are independent but the treatment 3 is the combination of the first two. I want to test ...
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Is there a non-parametric test to replace repeated-measures ANOVA in R?
I have a data set with 41 individuals, male and female, and 3 different measurements of a variable for each individual. The data is not normally distributed, nor does it have equal variances between ...
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Accounting for non-independence of measurements in analysis of variance
I have 10 measurements for each of 50 patients, each obtained at 3 different time points (i.e. 500 + 500 + 500 values). The measurements are of the same quantity but were measured in different ...
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Relevant statistical test for data of a ranking experiment
I'm currently thinking of a relevant statistical test to use to assess the results
of a small study.
Imagine i have 6 different brand of a food product and i want to know whether the participants to ...
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