Questions tagged [tukey-hsd]

Tukeys Honest Significant Difference (HSD) is a multiple comparison method based on the studentized range distribution.

Filter by
Sorted by
Tagged with
0
votes
1answer
291 views

Tukey-Kramer or Nemenyi following Friedman

I previously asked a question here after discovering an option by MATLAB to run Tukey-Kramer for multiple comparison multcompare following Friedman test and many ...
0
votes
0answers
243 views

What is the point in reporting the z statistic of a z-test?

In my field some authors report the z statistic of a z-test in a generalised linear model and others do not. Does reporting the z statistic serve any purpose if the p value of a z-test or of a post-...
2
votes
0answers
2k views

Two way ANOVA and post hoc test

I performed a two way ANOVA over a test set. My two nominal variables are treatment and clone. My outcome variable is area. ...
0
votes
0answers
340 views

ANOVA and tukey test on categorical variables

I have a data frame like the one below, I want to apply an anova test and tukey post hoc test analysis. ...
0
votes
0answers
77 views

A question about Tukey HSD test

Does Tukey comparison in glht/multcomp package in R refers to Tukey HSD test? Can I use the Tukey HSD test (for multiple comparisons) after applying the Robust technique (Such as Robust Anova, Robust ...
0
votes
1answer
108 views

How to state my model in R in words (linear mixed effect model, general linear hypothesis, Tukey, Benjamini Hochberg)

I have a dataset that has four treatment groups (AX, AY, BX, BY). I am trying to determine if there is a significant difference in a response variable (Length) between any of these four treatment ...
0
votes
1answer
910 views

Tukey HSD plot_simultaneous - how does it work?

I have performed a Tukey HSD in Python. I am not sure what values are plotted when using the .plot_simultaneous() command (see statsmodels documentation). The resulting plot is: I am wondering: how ...
1
vote
1answer
189 views

Are the results of my paired tests false positive?

I am dealing with a strange situation which I hope you can come up with a solution. I have 3 pared group(n=7 for each) which I tried to see if they are significantly difference and if so, in which ...
0
votes
1answer
394 views

How do I perform an ANCOVA ? (master thesis deadline) [closed]

My dataset consists of several morphological measurements for 5 island populations of a certain lizard species. I want to test for each population if there is a significant difference in the ...
2
votes
2answers
1k views

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 ...
1
vote
1answer
1k views

R Tukey HSD Anova: Anova significant, Tukey not? [duplicate]

i created a simple anova with three groups in R and get a significant Result. After that i do a Tukey HSD Test and now nothing is significant. How can that be? Pr(>F): 0.0316 Group | p adj 1 - 2 ...
2
votes
1answer
3k views

What are the (practical) differences between Tukey's HSD and the Dunn-Sidak correction procedures?

I have a data set with three groups, one of which is a control and the other two groups have been administered either a moderate or a high dose of a drug. The data are not normally or log-normally ...
4
votes
2answers
807 views

Differing p-values car::Anova, anova & post hoc in logistic regression

I am currently working with a logistic model in R and I have a question regarding the p-values that I get from different types of tests. Since I have separation in my data (caused by X) I use the ...
2
votes
1answer
2k views

Which one to choose Type-I, Type-II, or Type-III ANOVA? [duplicate]

I don't understand what the difference is between TypeI and TypeIII? Since my background is not very mathematics, it's very difficult for me to understand this mathematical notation; Type I SS: SS(A) ...
2
votes
0answers
411 views

Power analysis for one way anova with post hoc Tukey?

I have an experiment in which I'm doing, among other things, a One way Anova with one dependent variable and 5 groups. After the ANOVA i'm doing Tukey's post hoc to test for differences between groups....
4
votes
1answer
4k views

Why do planned comparisons and post-hoc tests differ?

I conducted a three-way independent ANOVA. I manipulated the sound of my stimulus to be 1: congruent (KON), 2: incongruent (INK) and 3: no sound at all (control condition). One of my planned ...
2
votes
1answer
227 views

Comparing different treatments using logistic regression

I have some data on testing different pesticides on insects. I have applied different concentrations and different pesticides (total 11 treatments) for 24 hours, and have 6 different data points. I'm ...
0
votes
1answer
118 views

Adjust for multiple comparisons in several mixed models

I am fitting several generalized mixed models with binomial family to model proportions data(dependent variable) and 3 factors.The data looks like this: Sample Day ligand Condition Conc1 Conc2 .... ...
1
vote
1answer
328 views

Interpreting ANOVA, Tukey, Linear Mixed-Effects Results

I am trying to follow the work of a scientist who compared two factors (A and B) each with two levels. The general output from R appears as follows: ...
2
votes
1answer
130 views

Why “Honestly” in Tukey's Honestly Significant Difference (HSD)?

Why is the word "Honestly" in "Tukey's Honestly Significant Difference"? It seems unusual. Most statistical procedures are developed with the intent to give an "honest" answer. Why is that word ...
2
votes
1answer
4k views

Post Hoc Pairwise Comparison of Interaction in Mixed Effects (lmer) Model

I have searched other posts and textbooks and found numerous variations of the pairwise comparisions for my mixed effects model using code from the multicomp ...
0
votes
3answers
112 views

Is this an example of a multiple comparisons problem?

I am conducting a comprehensive research determining the effect of 3 independent variables on the metabolic rate of an organism. However, the set-up of my data analysis leads me to believe that I ...
2
votes
1answer
4k views

Tukey with interaction and extracting letters in multcomp

I've seen similar questions posted elsewhere with no answer, so I thought I'd put this out into the CrossValidated universe. I am attempting to do a Tukey's post-hoc test on a model that has an ...
2
votes
1answer
204 views

Possible to have insignificance when two groups have non-overlapping 95% CI for Tukey test?

I am comparing three group means (95% CI), as following: A (n=248) B (n=1000) C (n=102) 1.3 (0.6-2.1) 3.9 (3.1-4.7) 2.5 (1.2-3.9) There ...
0
votes
0answers
29 views

how to find which row is significantly different

I have a data which looks like this ...
0
votes
1answer
604 views

One-way ANOVA, clustering levels using Tukey Kramer HSD

Suppose I am doing a one-way fixed effect ANOVA on an unbalanced data set. Let the number of levels of the one way factor be "a". Suppose the omnibus null hypothesis is rejected. So I do a post hoc ...
2
votes
0answers
145 views

Should I use post-hoc tukey HSD or some other test for pairwise comparisons of a factor on a zero-inflated negative binomial mixed model (ZINB)?

I ran a zero-inflated negative binomial mixed model (ZINB) and now have a statistically significant factor (recording type, either NOCA, BCCH, or Human). To assess the differences between these three ...
2
votes
1answer
3k views

Paired t-test and Tukey post hoc

I am running a repeated measures anova. Once I get significant p values, I run paired t-tests and I also apply Tukey post hoc. The fact is that I get lower p values with Tukey than with paired t-...
1
vote
0answers
347 views

Compute the power of Tukey's Honest Significance Difference (or cognates)?

I've got a simple computational model I can run experiments with. Experiments are "free" but I don't want to run it more times than necessary because it still takes time. All the simulation use the ...
2
votes
1answer
86 views

How to do Post hoc tests

I have conducted an experiment with 12 conditions (1 baseline). One of the response variables is binary, others 7 point Likert scale. I want to test all other conditions against the baseline (11 ...
1
vote
0answers
998 views

Post-hoc tukey test after repeated measures ANOVA in R taking into account spherecity

I am trying to do some repeated measure anova in R. Consider the following data. ...
2
votes
1answer
1k views

How to interpret grouping result in Tukey's HSD test

Assuming there are three methods to kill bugs, and we want to know whether their performance differs. The Tukey's HSD test gives the following grouping results: ...
0
votes
1answer
214 views

Easiest way to run an unbalanced 2-way ANOVA

Trying to help a friend out who has no idea about statistics but who has to compare a few samples for a medical paper. So we have 6 different types of fingers which underwent 3 different treatments. ...
0
votes
1answer
1k views

question about ANOVA post hoc analysis

I understand that people use Games Howell, Tukey or sometimes pair-wise t-test (with correction) test as post hoc analysis procedures following one-way ANOVA. My question is following. For example, ...
0
votes
1answer
76 views

Post-tests for mixed-model ANOVA in R? (Without installing packages?)

(Question originally posted on StackOverflow but users advised it was more appropriate to ask here:) I’m just starting out with R so I apologise if this is a silly question, however I have Googled it ...
2
votes
1answer
719 views

Tukey's comparisons for proportions

Question: What is an appropriate extension of Tukey's method to proportions? Normal situation In one-way ANOVA problems $$ y_{ij} = \mu_i + \epsilon_{ij}, \quad i=1,\ldots,m $$ Tukey's studentized ...
2
votes
0answers
459 views

problems with HSD.test

I would like to do a HSD.test. I have found an example of this and this example is working fine. This is the example: ...
1
vote
1answer
2k views

Interpreting compact letter displays and Tukey multiple comparisons from glmm

I am conducting Tukey HSDs with compact letter displays on a series of glmms. One example is how the presence/absence of ticks on an animal varies based on several parameters (using ...
0
votes
1answer
41 views

Clarification regarding One Way ANOVA in SPSS

Just wanted to ask everyone on here if I got the right idea. I'm doing research on algal cultures and I have data from 6 treatments which have three replicates each. A friend of mine did similar ...
1
vote
1answer
3k views

How would I interpret this TukeyHSD result in R?

I'm comparing two systems to see whether there is a significant difference in being able to locate anomalies using System A and System B. I've run a t-test on both and have rejected the null ...
0
votes
1answer
962 views

What are the drawbacks and benefits for the Bonferroni Adjustment, Fisher's LSD, and Tukey's HSD procedures?

When do you use which test and which test is best for isolating the differences in multiple comparisons?
3
votes
1answer
120 views

What's the correct method to rank populations?

I want to rank ten or so sources based on their respective error measurements. A few notes on the sources and measurements: The sources do not have the same number of measurements The number of ...
1
vote
1answer
177 views

How can I reproduce TukeyHSD's difference of means?

My data set comes from a series of five three-way full-factorial experiments, several of which are unbalanced. The three experimentally manipulated factors have two levels each. I am using R to ...
0
votes
1answer
270 views

p values all = 1 from glht Tukey following negative binomial glmm

I have an issues with corrected p values from glht Tukey. When I use adjusted p values using the Holm method all p values = 1. If I do not adjust p values the issue goes away. I'v trawled online but ...
1
vote
1answer
355 views

bootstrap or tukey's hsd?

I have several groups of measurements like shown below, and I want to know of the distance from each group to the overall mean is significantly different from the rest. Can I do a bootstrap where I ...
1
vote
1answer
536 views

lsmeans pairwise contrasts not computing all comparisons

I performed mixed model ANOVAs using the lmer function from lme4. My model is as follows. ...
7
votes
1answer
37k views

Interpreting TukeyHSD output in R

I performed a simple ANOVA in R and then generated the following TukeyHSD() comparisons of means: I have a pretty good idea (I think) of what all this means except the 'p adj'. If I'm correct: The ...
0
votes
0answers
60 views

Mixed model not finding significant differences but post-hoc comparison test is

I am running a mixed model on something akin to this data: ...
3
votes
2answers
352 views

I have significant differences detected in my glmer model summary but not in my mcp (Tukey) multiple comparisons summary. Why?

I am working on a project looking at ant recruitment to bait in the lab. I want to see which baits ('treatment') the ants recruit to more/less and have multiple measurements for each colony over the ...
1
vote
0answers
169 views

Tukey HSD pvalues in R

I have the following subset of dataset which I am using to create a boxplot (using ggplot) between study and FPKM: ...