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Questions tagged [tukey]

The Tukey test is a single-step statistical test for multiple comparison, named after John Tukey. It is used to find significantly different mean, by comparing all pairs on means based on a studentized range distribution.

The Tukey test is a single-step statistical test for multiple comparison, named after John Tukey. It is used to find significantly different mean, by comparing all pairs on means based on a studentized range distribution.

Assumptions

  1. Independence of observations within and among groups
  2. Normal distribution within group
  3. Equal within-group variance across the groups (Homogeneity of variance)

Also known as:

  • Tukey's Honestly Significant (Difference) test
  • Tukey HSD test
  • Tukey-kramer test/method
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"Contrast Error" message with lsmeans Tukey Test on GLM

I have defined a generalised linear model as follows: glm(formula = ParticleCount ~ ParticlePresent + AlgaePresent + ParticleTypeSize + ParticlePresent:ParticleTypeSize + AlgaePresent:ParticleTypeSize, family = poisson(link = "log"), data =…
tiptothetop
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How to compute Multicompare Tukey HSD in python?

I am trying to compute a multicompare Tukey test with a list which contains 5 list of values (it is a list of lists). I was reading some documentation about numpy.recarray which it seems to fit in this topic but I don't really know how it works.…
Steve Jade
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Compare means for only certain group combinations

The data looks as follows: > data <- read.csv("data.csv") > head(data) ï..class.1 rev.1 class.2 rev.2 1 7 136.9900 1318 31.9900 2 1223 24.0984 1001 0.0000 3 1318 61.9900 6851 104.2655 4 1014 39.9800 …
Sharkbait
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TukeyHSD or glht in R, ANCOVA

I'm wondering if i can use the function "TukeyHSD" to perform the all pairwise comparisons of a "aov()" model with one factor (e.g., GROUP) and one continuous covariate (e.g., AGE). I did for example: library(multcomp) data('litter', package =…
Sue
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plotting letters with ggplot geom_text in two-way anova

I'm trying to plot the significance letters with TukeyHSD, in a two-way anova, but have only found information for a one way anova. I'd like to have letters for comparisons within each group, such as within Gene1 and within Gene2. create…
Canteen9
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Post-tests for mixed-model ANOVA in R?

I’m just starting out with R so I apologise if this is a silly question, however I have Googled it extensively and can’t seem to find an answer. I am attempting to analyse data with structure: 'data.frame': 60 obs. of 4 variables: $ response:…
Mel
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renaming many levels of a factor - R -

I am trying to rename the names of all the level of my factor variables, so I can run TukeyHSD. Tukey procedure doesn't like when levels are named by numbers. Therefore, I do not care about the name per se, I only want the name to be a character -…
Nneka
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How to perform Tukey comparisons with linear model including three double interaction terms?

I'm trying to analyse some data where I have three explanatory variables named Estimulo, Velocida, and Viendocon (all of them to be taken as factors) and one response variable, named Vueltasmin, which is a numeric one. As I measure Vueltasmin after…
ybarnatan
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Mixed Model [in place of Repeated Measures ANOVA], but need RANKED Tukey results PER sampling date (NOT overall)

I have data from 6 different treatments, with sampling repeated 8 times over 3 years (no missing data points). My individual bins from each treatment are equally split in 7 randomly distributed blocks. To analyze, I am using a Mixed Model…
K_R
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Loop through several post hoc tests in R

I have a dataframe called data. I have created a function that loop thorugh a list of variables and creates a linear model for each of them using lapply. This method is based on this post. library(datasets) testDF <- data.frame(Salaries) #creates…
Lars Christian Jensen
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How to incorporate "significance" of a Tukey'sHSD directly into graphs of ggplot2 in R?

I have the following data(dat) V W X Y Z 1 8 89 3 900 1 8 100 2 800 0 9 333 4 980 0 9 560 1 999 I wish to perform TukeysHSD pairwise test to the above data set. From the results of the test, I want to incorporate the…
Rspacer
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How to order groups when using HSD.test() from the Agricolae package?

my question about displaying the homogeneous subsets after a Tukey HSD test is already been asked in the past (see https://stats.stackexchange.com/questions/31547/how-to-obtain-the-results-of-a-tukey-hsd-post-hoc-test-in-a-table-showing-groupe, at…
Jelle
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How to run and annotate separate TukeyHSD for individual facets in ggplot2 boxplot?

I am not very good at R and am trying to pull together this code that is not quite working out how I would like it to. I would really appreciate any help on this! I would like to perform TukeyHSD test among treatment groups in individual facets in…
Hazel Wassername
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increasing the resolution of the p value on a Tukey test in R

I performed a Tukey HSD test in R, and I want to see the p-value of one of the comparisons. When I run the Tukey test, my p values are so small that on the table they just read as "0.0000000". I need to know what the actual value is, even if it is…
Emily
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Tukey test only plot significant mean differences

I tried to use the following code from a previous post: Tukey Graphing Problems in R SigOnly <- Tukey SigOnly$species <- SigOnly$species[SigOnly$species[,'p adj'] < .05, ] plot(SigOnly) But get the following error when trying to plot: Error in…
Carrie Perkins
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