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

learn more… | top users | synonyms

-1
votes
0answers
17 views

How do you do a log-linear analysis in r? [on hold]

I can't seem to find anything on log-linear analysis. Does anybody know how to do them in r? I have two variables: one a dependant one (yes or no recoded as 1 or 0) and an independant one with 5 ...
2
votes
0answers
11 views

Is there a consensus on adjusting alpha for multiple contrasts if the main effect is significant?

After talking to a couple of statisticians, reading some book sections, internet articles, and forums like this, I am still unclear about multiplicity adjustments of post hoc tests and contrasts. ...
0
votes
0answers
11 views

Explaining mixed-model interactions with ANOVA?

I have searched through the answers on this forum and I couldn't find any detailed explanation to my question about linear mixed models. Here is my setup: 4 groups with treatment X (one of which is ...
1
vote
1answer
25 views

Most appropriate test for my data?

I am strugling with my current science project on how to determine statistical significance among my tested groups. I have however a very basic understanding of statistics and would like to understand ...
0
votes
0answers
19 views

EMMEANS Pairwise Comparison OR Post Hoc Multiple Comparison?

I was running a 2-way Univariate ANOVA, and there are two tables in the results that compair the 3 levels of one of my IVs (Transformation_Model). Under Estimated Marginal Means, the table is titled ...
0
votes
1answer
33 views

Post-hoc testing in multcomp::glht for mixed-effects models (lme4) with interactions

I am new to CrossValidated, so if there is a better way for me to format or ask my question, please feel free to comment. I am performing post-hoc tests on a linear mixed-effects model in R (package ...
0
votes
0answers
23 views

Are the statistical words contrasts and post hoc synonymous?

I have implemented a linear mixed-effects model using lmer{} model in R and used glht to to ...
1
vote
1answer
19 views

Bonferroni method for multiple comparisons with 1-way layout

My statistics book describes the Bonferroni method of doing multiple comparisons with a one-way layout as essentially performing a t-test with each pair of interest with a significance level scaled ...
0
votes
2answers
56 views

Post hoc analysis for linear mixed model with nested effects

I'm having trouble in R with my Linear Mixed-Effects Model. I'm working with yeast in nectar. This is a part of my data just so you can see what is going on: For the condition sucrose, I have 4 ...
0
votes
0answers
14 views

Post-hoc test for prop.test with 3 samples

I am performing a prop.test() in R for 3 different groups (samples). The result is a p-value that tells me that the observed proportions differ between the groups. --> How can I now find out whether ...
3
votes
1answer
134 views

What is the difference between various Kruskal-Wallis post-hoc tests?

[There seem to be a lot of similar questions here, so please point me the right direction if this has already been answered, but I think it's reasonably differentiated.] There are many different ...
0
votes
1answer
20 views

Post Hoc Analysis in Mixed linear models

I tested whether different version-styles of a loading screen (hourglass vs. progress bar) in different progression patterns (linear, accelerate, decelerate, irregular, binary) affect time estimations ...
0
votes
0answers
16 views

Post-hoc test on 3 groups comparison

I have 3 groups each with 6 values. After performing acceptable levene test for Homogeneity of Variance, I performed Anova on my data. It was significant, and I started to perform post-hoc test. The ...
4
votes
1answer
60 views

MANOVA multiple comparisons with equivalence testing

For a MANOVA with $n$ variables, I would like to do pairwise comparisons between $k$ levels for one of the variables. What is the suitable method to adopt for ...
0
votes
0answers
15 views

Why is it inappropriate to use a post hoc test on a random effect?

This is a bit more conceptual, but I know its incorrect to run a post hoc test on a random effect, though I'm not entirely sure as to why. I figure it has to do with the selection of random variables, ...
0
votes
0answers
45 views

Fisher's exact test for 3x5 contingency table in R with post-hoc? Consistently with using Fisher or Chi-squared?

I'm struggling with some (relatively simple) stats questions for some work I'm doing in R, and can't seem to find answers online... I have a factorial response variable of habitat type of a species ...
0
votes
1answer
47 views

How can I interpret a significant one-way repeated measures ANOVA with non-significant pairwise, bonferroni adjusted, comparisons?

I have a dataset with one factor consisting of four levels. I've run a one-way repeated measures ANOVA on the data, which came out significant. However, for the follow-up pairwise, bonferroni ...
0
votes
1answer
50 views

nlme fixed effects analysis recommendations

I have only a very basic background in statistics, and I have a possibly simple question, but I'm having a bit of trouble with my model. I suppose this is also an R question, but also statistical! ...
4
votes
1answer
171 views

Post-hoc test for chi-square goodness-of-fit test

I'm conducting a chi-square goodness-of-fit (GOF) test with three categories and specifically want to test the null that the population proportions in each category are equal (i.e., the proportion is ...
0
votes
1answer
54 views

Can assumptions of a statistical test be tested post-hoc?

Suppose I ran 100 1-factor ANOVAs. I find some significant results. Now, since ANOVA has some assumptions, I should test if they hold. So, can I run for example Levene's tests (to check equity of ...
0
votes
1answer
51 views

Tukey's test on two way ANOVA

So I have done a two way ANOVA, and would like to do a post-hoc Tukey's HSD test. What should I use for the $k$, SE, degrees of freedom and what is my $q$ and HSD? The exp is done in 4 places with ...
0
votes
0answers
41 views

Post-hoc analysis

Ok so maybe stupid question but I need to know, if im doing a post-hoc, and my experiment has two sources of variation, and one of them is significant and one is not. Do I only look at the means of ...
0
votes
1answer
74 views

Post-tests to consider in mixed models

I have a mixed model of the form y~condition + Replicate + Error(Replicate) but at the moment, and am running into difficulties in performing a post-hoc test. I ...
2
votes
1answer
71 views

Multiple comparisons with many groups

I would like to determine if using multiple comparisons test would be appropriate for my data. I used the Kruskal-Wallis test to determine if there were differences in mean inhibition among $17$ ...
1
vote
1answer
152 views

Bonferroni correction on multiple Kruskal-Wallis tests

My data consists of 3 groups, and 6 variables. The data are not normal so I want to use non-parametric tests to uncover significance. The first thing I wanted to get your opinion on is, is it ...
2
votes
1answer
331 views

How to follow up a factorial MANOVA with discriminant analysis?

This is a follow-up to to my previous question: How can MANOVA report a significant difference when none of the univariate ANOVAs reaches significance? I have two IVs with each having three levels ...
2
votes
0answers
49 views

ANOVA P-value adjustments for semi-continuous data

In tests such as the Bonferroni post-hoc p-value adjustment test, convention is to correct the data with a constant, equivalent to the length (number) of pairwise comparisons that are being performed. ...
7
votes
2answers
301 views

What is the problem with post-hoc testing?

My statistic professor says so, all the books that I look at state it: post-hoc-testing is unscientific. You must derive a hypothesis from theory first, and then collect data and analyse it. But I ...
2
votes
2answers
96 views

Minimum sample size for 1 way ANOVA?

I have tested a group of participants over various time points and I want to investigate whether mean score on each subsequent time point is significantly different to the mean score at baseline (eg. ...
0
votes
0answers
19 views

post hoc nested

Hy, need to do post hoc test for nested factor in SAS. I have two factors, A and B with B nested within A and I want to perform post hoc test in GLM in SAS. Is it possible? Stevan
0
votes
0answers
30 views

What type of post hoc test does a LME use by default?

I need to know what type of post hoc test a LME model is using in R, by default? Is it Tukey? And is the alpha modified?
2
votes
0answers
172 views

Converting Chi Square Adjusted Residuals to p values

I am running a chi squared analysis in SPSS on a 5 x 2 contingency table. The overall chi square p value was < 0.0005, so I ran post hoc tests (adjusted standardized residuals on the individual ...
0
votes
0answers
39 views

What is the relationship between degrees of freedom and number of comparisons in Nemenyi's post hoc test?

I have some data consisting of non-normally distributed samples drawn from one of several different groups. A Kruskal-Wallis 1-way ANOVA rejects the null hypothesis that the medians of the groups are ...
2
votes
1answer
51 views

Can I justify using a one-tailed test in for this interaction effect?

I have an experimental setup with 2 factors, site and disturbance treatment. I have reason to suspect that plots at site A will be more affected by treatment than plots at site B. My response ...
0
votes
0answers
66 views

When an effect size has to be considered sufficiently large?

I submitted a paper in which I analyzed the data by a mixed design ANOVA. I reported generalized eta squared as effect size. After significant interactions, I conducted planned comparisons. A reviewer ...
0
votes
1answer
211 views

Post Hoc test after lme [closed]

I am trying to run a Post Hoc test (glht) after a linear mixed model (lme) in R. I was ...
3
votes
1answer
78 views

Post-hoc after GLM: What does it exactly say?

Background: I have been asked to model the change of weight of a few animals undergoing experimentation via a simple GLM (General Linear Model). The data looks something like this. Note that all data ...
0
votes
0answers
124 views

Post-hoc with Bonferroni a correction after ANOVA with repeated measure in SPSS

does somebody know where I can find the t value of post-hoc tests with Bonferroni correction when using SPSS.From what I get so far, I only see p values. Should I add a command in the script? Thank ...
0
votes
3answers
250 views

Testing and reporting interactions in multiple regression

I have a model with two between-participants predictors -- one continuous (a), and one categorical with two levels (b) -- and ...
0
votes
0answers
62 views

Can one make a Tukey post-hoc test for multiple regression in R and how?

I saw that the Tukey post-hoc test is usually done after performing an ANOVA. However, is it possible to carry it out in the case of multiple regression with the following model: ...
3
votes
0answers
80 views

Post-hoc power analysis of complex sample survey data

I am working with a complex sample survey data using Stata to determine the predictors of a given dependent variable. As part of my analysis result I want to report the post-hoc power for each ...
0
votes
0answers
56 views

Pairwise comparison of slopes from multivariate regression model in R

I am investigating size changes over time. I have five size variables in a multivariate linear model against year. I used the Anova() function in the car package to test whether the slopes are equal ...
0
votes
0answers
11 views

Follow up 2-way ANOVAs

I have a three-way significant interaction in a mixed-ANOVA, with two repeated-measures factors and one between-subjects factor. I would now like to follow it up with a repeated-measure ANOVA for each ...
0
votes
0answers
84 views

Post hoc for GLM that looks at interactions (in R)

I’d like some help with analysing some count data. I am very new to R (and statistical analysis for that matter!) and have done my best to work it out on my own … but seemed to have got stuck! I am ...
0
votes
0answers
32 views

How to use controls as a reference in GLM?

I'm running glms in R on two datasets, both with three discrete explanatory variables and one continuous dependent variable. My question is about the use of controls - I want to use my controls as a ...
0
votes
0answers
81 views

mixed design and simple main effect analysis in SPSS

Hope someone can help me. I have a within subject variable (Question, with 11 conditions) and a between subject variable (stimulation, with 3 conditions). I did an ANOVA and I obtained a main effect ...
0
votes
1answer
369 views

Which post-hoc is more valid for multiple comparison of an unbalanced lmer-model: lsm or mcp?

After doing a model comparison with my mixed lmer model, I have a model with three main effects, no interaction, say ...
0
votes
0answers
92 views

How do I report the result of an mcp-Tukey-test, i.e. how do I report it's z value?

After doing a model comparison with my mixed lmer model, I have a model with two main effects, no interaction, say signal ~ factor A + factor B + (1|subj). Factor ...
0
votes
0answers
69 views

GEE and post hoc comparisons

I am trying to analyze a dataset using the GEE. This is what I have so far ...
0
votes
0answers
52 views

Looking for a better post-hoc analysis

I'm a PhD student in Neuroscience, with a master degree in Psychology and I use R for my statistical analyses. As you know, in NHST usually post-hoc analysis in continuous data are essentially ...