Questions tagged [tukey-hsd-test]
Tukeys Honest Significant Difference (HSD) is a multiple comparison method based on the studentized range distribution.
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Meaning of "Unbalanced" Tukey HSD in R with Agricolae
The Agricolae package in R contains a function HSD.test which performs Tukey's HSD. This function has a parameter ...
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What is the best post-hoc test to use after a two-way anova has shown there is only a significant effect when including 0 as a factor level?
I have two factors: A and B, and a response, y.
For factor A I have 3 levels: 300,400,500.
For factor B I have 3 levels: 0.5, 0.6, 0.7.
I carried out an experiment with each combination of these two ...
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Tukey's HSD after permutation tests. Theoretically possible?
I'm interested in making more use of tidymodels' infer package, which lets one perform a variety of statistical tests by a simple algorithm. Here's an example pipeline for an F-test, where we aim to <...
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Post-hoc table in statistics
Please can someone help me interpret what the asterixis mean and how it is statistically different to the groups. I am so confused. I am doing a one way ANOVA looking at the effect of age on physical ...
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Help interpreting zeroinfl results from emmeans
I am working on the example Senecio data from Blasco‐Moreno et al. (2019) using the pscl package in R. I would like to conduct pairwise comparisons of mean rates (Damaged/Total_heads) and don't ...
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Is one-way ANOVA + Tukey HSD a good choice for significant test for data with different orders of magnitude?
I'm here to receive some information regarding the application of a statistical test of significance for this type of data.
The example shows the values of the peak areas of a given cocoa molecule ...
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Confidence interval for difference of means for TukeyHSD vs two-sample t-test?
I have some data with categorical predictors and I'm wondering about comparing the confidence intervals of difference in means of one pairwise comparison in my TukeyHSD analysis vs that of a two-...
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The theory behind Tukey's HSD test.
I have not been able to find satisfactory explanations for the logic behind Tukey's HSD test.
However, the resources I have been able to find all concern it's use. It's supposed to make multiple ...
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How is $q_{\alpha,k,N-k}$ in Tukey's test calculated?
On the wikipedia page for Tukey's range test, under section Confidence Limits, a quantity
$$q_{\alpha,k,N-k}$$
makes an appearance. Unfortunately, it is not defined ...
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approximating the density of the studentized range distribution
Is anyone aware of an approximation to the density function for the studentized range distribution https://en.wikipedia.org/wiki/Studentized_range_distribution ? I've found a fast approximation for ...
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Pairwise comparison; Tukey HSD or FDR
I have a general question about running multiple pairwise comparisons. I did some genetic work in grad school, where we (I believe) utilized a statistical test (Student's T-test?) followed by a FDR-...
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How to get the group differences after Bonferroni correction in multiple comparison?
After an ANOVA in R, do you know if it is possible to get the group differences using Bonferroni correction ?
If I use the iris dataset
...
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One-way ANOVA F-test is significant but none of the Tukey pairwise test is significant
I made up this example myself: Three geoscientists from China, USA and Europe were interested in exploring the mineralogical and textural characteristics and organic carbon composition of carbonate ...
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R Tukey Anova: Can non-overlapping boxplots share the same letter of significance in Anova / Tukey Test?
I conducted a one way anova followed by a tukey-test in Rstudio and used a compact letter display to add letters of significance to a ggplot.
After a positive Grubbs-outlier-test I removed an outlier ...
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How do you know the difference between groups with TukeyHSD in Python?
*Assume that we conducted an ANOVA test, and we have a difference.
Now let's say we measured the difference between groups (countries in my case), and Python outputted the following table (it's a ...
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Tukey test for glm of catch data and fitting glm?
I have angler catch data from tournaments over 10 years and want to compare the proportion of each species (Sp1 vs. Sp2, Sp1 vs. Sp3, Sp2 vs. Sp3) caught within each year 2005 to 2015. So were more of ...
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Can I use TukeyHSD to explore my anova interaction in an repeated measures 2 factor experiment? [duplicate]
I am very new to statistics. I have a within subjects, 2 factor experiment in which I will be required to explore an interaction. I was wondering if I can use the TukeyHSD test for this.
Any help ...
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One-way ANOVA for multiple features?
I have 60 continuous features (i.e., lab results) for 35,000 patients, and the patients are divided into three groups. I want to evaluate each feature to find out what the differences are between the ...
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Repeated measures ANOVA with significant interaction effect, but non-significant main effect
I am running a two-way repeated measures ANOVA (main effects: Time, Condition). The result is that the main effect of time is significant (P<0.05), the main effect of condition is not significant (...
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ANOVA Post-Hoc Tests Multiple Imputation Framework
I have a used miceadds::micombine.F() to pool F-statistics across multiple imputations. This gives me an overall F-statistic and a significance level for my ANOVA ...
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How to conduct a posthoc test on effect size from linear mixed effect model?
I have a linear mixed effect model with the following output
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How to summarise ANOVA post-hoc Tukey test?
I am having trouble to interpret tukey's post hoc result from the following
They incorporated post-hoc test results into a table using the 𝑎≤𝑏<𝑐 style notation (𝑎,𝑏,𝑐,... correspond to ...
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Interpreting categorical variables with reference level in linear model
I wonder how should I report the results of categorical variables with reference level in linear model?
The response variable of my model is Duration (time taken to reach 25C for an animal model). My ...
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Why is my Tukey post hoc test is not significant while my values are visually different?
can anyone help me to understand this.
I have data to compare among 3 experiments with 2 treatments each.I want to compare a measured variable between the 2 conditions for each experiment. I first ...
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How to determine how much variation was due to the differences between a group?
I am working on the data set that consists of Patients (after stroke), Time (then can walk after a going through the program), and Program they follow.
...
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R pairs function, adjust, tukey/tukey-kramer?
In the 'pairs' function when doing pairwise comparisons after emmeans, tukey is set as default for adjustment of p-values. But what type of tukey is used, is it tukey-kramer? How can I know this? If ...
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Evaluate significance for three different groups not normal distributed with different n
I have a group with three different treatments. One group gets shown 0 Tags, 4 and 7. N's are different in the range of 80-100 and data does not follow a normal distribution.
I would also like to ...
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What does p-value = 0.00e+00 mean? [duplicate]
I ran TukeyHSD test on a linear model which gives me a result with some p-value = 0.00e+00. Does this mean the p-value is very small hence it's significant? or there's error?
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Understanding the difference between linear and interactive terms in Tukey HSD
I have an analysis of a dataset with a factorial design. Currently, I've been doing the analysis in R, using aov and TukeyHSD. I ...
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Tukey HSD Post Hoc test with the Anova() Command (Car-package)
I am trying to do a Tukey-Test with the Anova() command from the car-package. I am using Anova() because I have an unbalanced ...
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Questions about plotting a two-factor anova
I have an experiment where I collected 36 water samples in three different streams (12 samples per stream). Subsequently, I divided these samples into 4 groups (3 samples per group), and treated them ...
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Multiple post-hoc tests after Multivariate GLM/MANCOVA
I have three groups, where I am doing a multivariate GLM/MANCOVA to test for multivariate differences between groups (6 DVs), adjusting for 2 covariates. I would like to do post-hoc tests to see which ...
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Using ANOVA and HSD, I find A and B are not significantly different from C, but I find A is significantly different from B. What does this mean?
I'm learning a bit about ANOVA and Tukey Range test and my understanding is if there's significance between two samples, they don't come from the same distribution. However, in some tests I'm having a ...
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Does $\alpha$ for Tukey change like it does for Bonferroni?
If you are trying to find confidence intervals, how does $\alpha$ for Tukey and Bonferroni differ? I understand that for Bonferroni the $\alpha$ is divided by the number of groups; however, does the $\...
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Effect size calculation for One-way ANOVA and Tukey-HSD
I'm calculating the minimum sample size to conduct a One-way ANOVA test that I will follow with a Tukey-HSD post hoc analysis. I'm using software R to do my calculations.
From the 'pwr' package, I ...
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One-way ANOVA followed by Tukey test - confidence intervals
I want to test 3 types of treatments (T1, T2, T3) along with a control/placebo treatment (T4). In order to do so, I'm performing One-Way ANOVA to my data and then proceeding to the Tukey test.
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Testing whether means of several gamma distributions are equal?
I have conducted measurements on bubble sizes on 20 positions in the same foam, each of the 20 positions following a gamma distribution. From the boxplot the mean values appear very similar... Now I ...
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Relationship between Q Studentized range and Student distributions
I was looking at the article about Tukey test on Wikipedia regarding the relationship between Q Studentized range and Student distributions and it look like
$\sqrt{2} t(1 - \alpha / 2, n-c) = Q(\...
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post-hoc (Tukey) on adonis (permanova) [closed]
I have a bray-curtis distance matrix and found significant associations on a grouping variable with adonis (permanova) using R package vegan. Now I would like to perfrom a post-hoc test to test ...
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Unclear why "adjust = "tukey" was changed to "sidak""
I noticed a strange behavior for cld function when making multiple comparisons.
When I use cld(EMM, adjust = "tukey") ...
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I got the same adjusted p values (p adj) at different confidence levels (conf.level=0.95 and conf.level=0.90) when I run TukeyHSD in R
I am learning the TukeyHSD in R. The following operations and results got me confused. I got the same adjusted p values at different confidence levels (0.90 and 0.95). Should the adjusted p values ...
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Studentized range table - reported paper value does not match table
I'm reading a paper on multiple comparisons (citation below). The paper reports (page 324, step 5) that we need to:
"Find the percentage point of the studentized range (SR_n) corresponding to a ...
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Tukey Test and Linear Regression
Say there are four groups, (a,b,c,d), for one feature in a dataset with many features. I am trying to predict a numerical feature y. I perform the Tukey test and find that the means of y for groups a ...
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How do I interpret these colored bars and T's in this Tukey's HSD Plot?
This shows a box plot of value distributions for several variables. I know that the letters indicate plots that are too similar to distinguish at a 95% confidence interval. What do these ...
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Is the "mvt" (using the multivariate t distribution) accepted way of adjusting for multiple comparisons when reporting to journals?
I use the awesome package multcomp and emmeans in R. These are the places I heard about the "mvt" method for the first time. And, however, it is what it's actually done in the Dunnett or ...
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Tukey hsd test vs DMS test
I am analyzing the differences on my dataset. This dataset has different values according to each group (called season_sized). I have no normality and heterocedasticity, so I performed a GLM to fit my ...
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ANOVA F-test shows significant differences among treatments, but HSD.test does not: What is the reason for this discrepancy?
I am working with a dataset (in R) that has been hierarchically-clustered into three distinct clusters. My goal is to conduct a one-way analysis of variance to see if there are any statistical ...
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Comparison Circles algorithm in Python
My goal is to visually represent similarities between groups using the comparison circles algorithm described here: https://docs.tibco.com/pub/sfire-analyst/7.10.1/doc/html/en-US/TIB_sfire-...
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Post hoc test after Chi square, please advise [duplicate]
I am analyzing a questionnaire survey data about online learning receptibility across different age groups. I have 4 age groups, and each has its % acceptance of the online learning susceptibility. ...
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Comparing different samples from different years: ANOVA?
I have been collecting data for 10 consecutive years. Once in each year different participants (N=110/Year) had to rate the importance of each one of 30 different social values, on a Likert scale (1-5)...
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