Stack Overflow
Stack Overflow

Questions tagged [posthoc]

181 questions
0
votes
1 answer

post hoc results from emmeans does not reflect differences in data

I have a data with three factor variables: 1.) Item_Type: Factor w/ 4 levels "control","Ar", "Eng", "Fr" 2.) Time of Testing: Factor w/ 3 levels "Pretest","Posttest", "Delayedtest" 3.) Accuracy: Factor w/ 2 levels "0", "1" Item_Type and Time_of…
azizi tamimi
  • 53
  • 1
  • 8
0
votes
0 answers

Post hoc test for an ANCOVA with polynomial term

I have a model with an interaction term between a polynomial covariate and a factor. I performed an ANCOVA test and the interaction term was significant. Now I want to perform a post hoc test, but I can't figure out how to do that. I want to test if…
João Bosco Junior
  • 55
  • 5
0
votes
0 answers

Tuckey correction for planned contrasts with emmeans and pairs() in R

I have a mixed design with 1 between factor (Group: ASD, CTR) and three within factors (Time: pre, post; Trustee: good, bad; Step: 1,2,3,4,5). I performed a mixed model anova (type III) with aov_car: anova <- aov_car(rating ~ time*trustee*step*group…
claudia
  • 1
  • 2
0
votes
1 answer

Post hoc for binary GLMM (lme4) and plot

So I'm an R novice attempting a GLMM and post hoc analysis... help! I've collected binary data on 9 damselflys under 6 light levels, 1=response to movement of optomotor drum, 0=no response. My data was imported into R with the headings 'Animal_ID,…
Lois Flounders
  • 1
  • 2
0
votes
1 answer

output of variable names in looped Tukey test

I'm doing multiple TukeyHSD tests by looping through all dependent variable names as in the code provided by Eric Lecoutre in this thread: Loop through several post hoc tests in R It works very well, so thanks Eric! But in the output the variable…
yuqia
  • 1
  • 1
0
votes
1 answer

Dunnett test for mixed effect model of incomplete block design in R

(First question here on SO, apologies for any mistakes!) I'm trying to analyse data with a linear mixed model accounting for block (Plot) and genotype (Line) effects with Welch-Satterthwaite adjustment of degrees of freedom to account for the…
steven3ver
  • 1
  • 3
0
votes
0 answers

Games-Howell Post-Hoc Test in userfriendlyscience package: no output, just NA

I am running a one-way ANOVA in R and the homogeneity of variance assumption is violated. After running a signficant Welch's test, I am trying to run Games-Howell Post Hoc test in R. I am using the oneway function in the userfriendlyscience package.…
Haley Umans
  • 1
  • 3
0
votes
1 answer

R: post-hoc comparisons using estimated marginal means but not assuming equal variances

I am trying to use R to run post-hoc comparisons following a significant interaction for a mixed-method Anova. I would like to do the post-hoc similar to SPSS [EMMEANS=TABLES(Group*time) COMPARE(Group) ADJ(BONFERRONI)], using estimated marginal…
CRI
  • 53
  • 5
0
votes
1 answer

specs argument in emmeans function with R

I'm trying to figure out to do posthoc test in R with emmeans function from emmeans package. However, I couldn't find out what should I put in specs argument. as far as I understand it is where I put the variables that I want to contrast (my…
Erdem
  • 45
  • 8
0
votes
1 answer

"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
  • 1
0
votes
1 answer

extracting letters from LSD.test output in agricolae

I'm using LSD.test in agricolae packages Below is a reproducible example library('agricolae') group <- c(1,1,1,2,2,2,3,3,3) variable <- c(1,2,1.5,10,11,12,22,23,21) df <- data.frame(cbind(group,variable)) model <-…
osbwh
  • 49
  • 8
0
votes
2 answers

Letters group Games-Howell post hoc in R

I use the sweetpotato database included in library agricolae of R: data(sweetpotato) This dataset contains two variables: yield(continous variable) and virus(factor variable). Due to Levene test is significant I cannot assume homogeneity of…
David
  • 45
  • 2
  • 9
0
votes
2 answers

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
  • 36
  • 1
  • 5
0
votes
1 answer

Lsmeans producing identical p values when controlling for two other factors

Previously I have had no issues when using lsmeans to identify significant differences between groups while controlling for other factors using lme4 models. However, with the following dataset looking at fluoresence lsmeans produces identical p…
kris sales
  • 3
  • 1
0
votes
1 answer

post hoc for specific pairwise comparisons after welch's anova

I am quite new to R and completely new to this website, so I really hope I am ably to convey my question in a clear way. The following is a part of my data set: A1<-c(0.308, 0.3624, 0.1861, 0.6176, 0.0506, 0.1014, 0.2245, 0.1894, 0.246,…
OCSee
  • 35
  • 8
1 2 3
…
12 13