"post-hoc" refers to analyses that are decided upon after the data has been collected, as opposed to "a priori".

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Test for difference in a set of post hoc tests

I have calibrated an classifier with different sources of training data and I want to evaluate its performance with several data sets. I plan to use the Friedman test and post hoc Nemenyi tests to ...
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7 views

Conditional t-test

My question is perhaps on the abstract side: Suppose you plan on performing two t-tests. Test 1 is performed at alpha=0.05. You will only perform test 2 if the results of test 1 are significant. ...
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181 views

Does Bonferroni apply to inference from parametric and non-parametric models?

I have run 6 independent-samples t-tests, and 4 Mann Whitney U tests. When applying Bonferroni correction, does it apply across all 10 tests? My hypotheses are that there will be 4 significant ...
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3 views

Post-hoc for independent t-tests for a total scale score and subscale scores

I'm comparing two groups on scores on the Dissociative Experiences Scale, and its subscales, using independent-samples t-tests. The DES is a 28 item questionnaire yielding a total DES score. There are ...
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1answer
33 views

Which R statistics tests to use in order to compare the effects of different variables on a test score

cross posted from StackOverflow I'm hoping someone can help point me in the right direction. I've got a data set which includes 'testscore', 'User Type (a or b)', 'Gender' and 'Age Group'. The data ...
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5 views

Tukey HSD for multuple variables and single variable giving different results [duplicate]

I have tried to run Tukey HSD for multi-variable dataset. However, when I run the same test on a single variable, the results are completely opposite. To be more specific: code: ...
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19 views

Post hoc test in mixed ANOVA

I use STATISTICA Statsoft to make mixed ANOVAs (module for GLM). I`m not a professional neither in statistics nor in programming, so I may ask not very smart question. The situation is following: I ...
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18 views

Understanding Tukey post-hoc Tests for factor variables in GLMs

I performed a GLM, which contained one factor variable (Site), one continuous variable (Days_til_clutch_comp), and an interaction of two factor variables (Host * Egg_type). The levels of Site are: ACT ...
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1answer
52 views

Which multiple comparison method to use for a lmer model: lsmeans or glht?

I'm analyzing a data set using a mixed effects model with one fixed effect (condition) and two random effects (participant due to the within subject design and pair). The model was generated with the ...
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20 views

lsmeans multicomparisons and Fishers LSD

I am using the lsmeans package for "post hoc" multicomparisons and I read here: ANOVA - Do we need a global test before post hoc tests? that in general post hoc tests are valid even if the ANOVA ...
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9 views

SPSS Friedman post-hoc - determining best classifier

I'm a newbie, so sorry if the question is too straight forward. I'm comparing 5 algorithms on 10 different data sets. In SPSS I did a Friedman test, and the null hypothesis is rejected. Now I would ...
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1answer
15 views

Anova and post-hoc's vs CI's

I'm wondering about the use of anova and post-hoc tests versus CI's. If I have a three-way anova design (age group, sex, strain) with n replicates within each cell, the common way to analyze it would ...
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10 views

how can I interprets my data if I have a significant difference with an ANOVA but not in the post-hoc results?

I've analyzed the number of contacts that divers of different certification levels have done with the reef and there is a significant difference. When I run the post-hoc test for pairwise comparison, ...
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11 views

Chi post-hoc OR Z cell comparisons: do 2 proportion z-tests indicate most significant factors?

Attached is an example of some data I'm working with. I'm testing the occurrence of a rare behavior, while controlling for both education and the "bin" variable. The observed sample size is 129. This ...
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19 views

Anova and post hoc test show no significance, but box plot and an unpaired t-test shows differently

I have just preformed a one way anova for 9 treatments and one IV. The p value came back as 0.305. And although it is saying there is no significance I went ahead and did a Tukey post hoc test to see ...
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11 views

What is the best approach to test 2 independent groups on 4 DV's?

So I have 1 IV that consists of 2 categorical groups. Both groups complete the same four tasks, the 4 DV's in my study which are continious. I planned a MANOVA, to see whether the DV's are different ...
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21 views

ANOVA and post-hoc analysis preconditions

I know that before performing a t-test it's necessary to check if the data are nearly normal and that are not too skewed and also that we can relax the skewness condition as we collect more data. I ...
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34 views

R - Post-hoc test on mixed design ANOVA with variable n's

I am attempting to perform post-hoc tests on a mixed-effects ANOVA, and I am running into issues with the typical R-based solutions, which I think stem from the fact that the groups in my ...
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22 views

Factor in linear mixed model is significant, but none of the contrasts?

So I have a linear mixed model with two fixed factors, let's call them A and B, A has three levels (A1,A2,A3) and B two (B1,B2). There is also a random effect, let's call it subject. Over likelihood ...
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1answer
29 views

Can you use TukeyHSD as a post hoc test for a mixed model?

I completed a mixed model with repeated measures. I did an ANOVA comparing my model to a null model and got a significant value. Now I need to identify where those significant differences are in my ...
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17 views

Subgroup differences after group differences analysis

I have two main groups of subjects: no treatment vs treatment. Each group has an equal and large number of subjects. In the treatment group there are 4 subgroups, which have slight differences in how ...
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57 views

Post-Hoc test on a Poisson regression

Question How can I perform a post-hoc test after a Poisson regression to know which group differ from which other group? Dummy Data Here are some dummy data (coded in ...
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2answers
117 views

Post hoc power analysis for a non significant result?

I have submitted a paper to a journal reporting a non-significant finding. One of the reviewers has asked me to include a power analysis on my data to work out how big a sample size I would need to ...
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1answer
141 views

Interpretting non-contiguous significance letters from Tukey HSD test in the multcomp package? [closed]

I've only ever seen the compact letter display for Tukey's HSD give contiguous letter groupings but like in the following example this package is giving non-contiguous groupings (ie 'cde' is ...
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80 views

Interpreting output from lsmeans tukey test

I'm running post-hoc analyses on linear mixed models I ran for a dataset. I'm not totally sure how to interpret the output from lsmeans which is as follows: ...
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10 views

How do I manually calculate post-hoc tests of independence between all cells using output from SPSS complex systems module?

I'm trying to run post-hoc tests of independence between all cells using a data set that I need to run the complex samples module in SPSS. How do I use this output that includes population proportion ...
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33 views

How to discriminate among different post hoc friedman tests

I had to carry out several Friedman test comparing different yields. I also wanted to conduct a Post-hoc test to distinguish among different systems. I used the R function ...
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1answer
81 views

Post-hoc tests in mixed model using lsmeans and glht

I have a mixed model with two fixed factors (Insecte and temperature) with two random factors (bloc and date) nested in the temperature treatment. I also include interactions between the fixed factor ...
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43 views

What post hoc test should I run for a significant interaction in a two-way unbalanced ANOVA?

I have data with two factors (Category and Treatment) and each factor has two levels (A and ...
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54 views

ANOVA with Zero Variance

I have four sites. I would like to run ANOVA with Tukey's HSD post hoc test to show that an average hydrological variable (in this case peak runoff rate) is different across the sites. My issue is ...
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1answer
67 views

Interpretation of post hoc chi square test results

I have a $2\times 3$ table cross-tabulation. I've done a post-hoc test using SPSS but I don't know how to interpret the results. This is the output:
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40 views

Appropriate test for two test groups, one control group and binary outcome

I have the following problem: We send our Clients an email and offer them some new product. Let's say we want to test 2 email designs. Additionally, we need a control group, since some of the clients ...
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45 views

Conover and Nemenyi post hoc give different results

Using the Wine tasting data set as provided http://www.r-statistics.com/2010/02/post-hoc-analysis-for-friedmans-test-r-code i did Conover and Nemenyi post-hoc tests. They though give different ...
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35 views

Calculation of pooled variance for mixed effect ANOVA

I have an experiment with 1 within-subject factor, 1 between subject factor and additional factor of blocking (measurements were done in several separated blocks). I have used GLM module of my ...
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14 views

How to do a post hoc test on a linear model with interaction?

I am new and I don't have much experience with R. That's why all the previous posts about this topic seem to be too complicated for me to apply for my case. I have ...
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37 views

2x2 anova as post hoc test following a 2x3 anova

I did a 3x2 anova - my data looks like in the figure below I get significant main effects and a significant (3x2) interaction. I now want to test the interaction between the blue and green bars. So ...
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35 views

Post-hoc tests after within-between Two-Way ANOVA

I'm new here! I have run an experiment with two groups randomized to different experimental conditions (A and B), where an outcome parameter was measured at four time points (1h,2h,3h and 4h) I ran ...
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23 views

R: Dunnett's test gives z and t value

I am using R for statistical analysis of my data. For some experiments I have to construct a linear mixed effect model using the lmer function from the lme4 package. For other experiments an ANCOVA ...
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40 views

R: Confusion about research question using GLM

I have a dataset with 3 colonies (A, B and C, see below). Each colony is divided into 2 treatments: control and DWV. I use a GLM to test wether there is a difference of the life expectancy ...
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1answer
30 views

Post hoc test (lsm) gives unverifiable t and p values for my lmer model

I have a model of the following structure: lme4::lmer(formula = signal ~ factorA + factorB + factor C + (1 | subj), data = s) and find a significant main ...
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48 views

Complex Factorial Manova in R/SPSS

Hello I have been struggling for many days with this problem. The situation and data set are following. The data set comes from an experiment that asked subjects (ID) to compare several CVs on ...
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153 views

Post-hoc test for lmer

I am running mixed models using lmer, and am having trouble running a post-hoc test to look at the significance between variables. The first 5 rows of my dataset (out of 119) looks like this: ...
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0answers
17 views

Is merging two factors (one between and the other within) into one for the friedman test a valid strategy?

Accoding to what I have read so far, there is no straightforward way to perform a 2-way non parametric mixed design, except permutation tests - which doesn't solve my problem (i.e. I cannot find a ...
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2answers
432 views

Analyzing repeated measures experiment with multiple treatment groups and multiple measures

I am doing a study to evaluate the effect of two dietary supplements on body composition. Literature suggests that Treatment 1 (Dietary Supplement 1) affects body composition with some side effects ...
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2answers
196 views

Post Hoc Test of interaction factor in binomial glmm with proportions

I've performed a binomial glmm, because my data are proportions of a species in a sample of +/- 100 Individuals. I test the interaction of two factors and use car::Anova to get the p-values. My ...
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0answers
107 views

Kruskal-Wallis test + Nemenyi post-hoc test: further multiple hypothesis correction needed?

I have used a Kruskal-Wallis test in a one-factorial design with samples that do not meet the assumptions for one-way ANOVA. To do this I have used the function ...
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1answer
20 views

Low correlation coefficient, low p-value. Is there an alternative/supporting analysis?

I have ran a series of (Spearman) correlation analyses. The resulting statistics result in low correlation coefficients (i.e. <0.01) and low p-values (indicating significance). Is there post hoc, ...
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1answer
15 views

What test to use post hoc?

I have several scenarios in which I would like to do post hoc tests, but I am unsure of what tests to do. These are two way anovas with some of the interactions as significant and some of the main ...
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27 views

posthoc tests on a 3-way anova with trimmed means

I am performing a 2-way robust anova using the WRS2 package, t2way function with trimmed means and mcp2tm function for posthoc comparisons. The 2 way design is looking at the effects of temperature ...
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43 views

Post hocs tests after a two-way ANOVA (randomized complete block)

I ran a two-way ANOVA on my data : fixed factor of 8 df ramdom factor of 14 df My random factor are the blocks and my blocks have only one sample and I therefore didn't need my data to be normal. ...