All Questions
Tagged with lme4-nlme repeated-measures
377 questions
9
votes
2
answers
990
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Should I control for random effects of participant in an individual differences design?
I'm trying to analyse a survey study in which I'm interested in the way that individual differences between my participants influence how they respond to my stimuli. The stimuli are pieces of writing ...
CommunityBot
- 1
5
votes
2
answers
107
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Repeated measures within participant
I'm trying to learn linear mixed effects models and how to estimate them using the R package lme4 and I am confused about some aspects.
I have a dataset where a ...
- 2,391
3
votes
1
answer
303
views
Finding the optimal structure of fixed / random effects in a 3 way full factorial repeated measures design with nlme/lme4
I’m looking for help in finding the best / optimal structure of fixed and random effects in my repeated measures experiment data along with an explanation on why do I choose one solution over the ...
CommunityBot
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0
votes
0
answers
41
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How do I correctly formulate the random effects with repeated measures in a paired design
Sorry if this is a cross-posting, but I haven't found the exact solution for my problem yet.
Let us assume I have an experiment with 20 households, with 2 people each (1 female + 1 male).
Over the ...
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1
vote
1
answer
49
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How do I compute the intra-rater intraclass correlation for a study design with some repeated measures?
How do I compute the intra-rater intraclass correlation for a study design with some repeated measures?
The study had approximately 1000 subjects rated (continuously 0-100%) by 500 raters. Each rater ...
- 2,825
1
vote
0
answers
57
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Error in lmerTest: The random-effects parameters and the residual variance (or scale parameter) are probably unidentifiable
I know that there have been similar questions before, but I dont still get it.
I would like to estimate a multilevel model with repeated measures in R using the package “lmerTest”. The model ...
- 2,825
0
votes
0
answers
31
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Mixed effect model for two levels of repeated measures
I have a repeated measures dataset that I am attempting to analyze using linear mixed effects regression. I would like to compare the effects of different products (A and B) on a dependent variable (y)...
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7
votes
1
answer
1k
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Understanding Simpson's paradox with random effects
Simpson's paradox is well known as a situation where the correlation between 2 variables in groups (ie within-group slope) is of opposite sign to the overall correlationed between the 2 variables, ...
1
vote
0
answers
69
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Bread freshness in bread basket, Multi-Level Analysis in R; 2 time points [closed]
This is my first attempt with multi-level analysis.
My research question is;
How does the freshness of different types of bread (6 level) within a bread basket, change over two time points (ranging 4-...
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5
votes
1
answer
53
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Is repeated measures appropriate for testing for a difference in repeated paired group measurements?
I'm new to repeated measures and am trying to understand how it maps to lmer.
I have measurements from two time periods:
$t_1, t_2$.
At each measurement period, the same 50 different foods are scored ...
- 65.9k
2
votes
0
answers
86
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untrustworthy p values? emtrends following lmms with fixed effects of different levels of repetition
Edited to clarify further 23/04/24:
I have a fairly complex linear mixed effect model in R and I believe that there are issues to do with repeated data when running my post hoc tests. The model ...
- 21
0
votes
1
answer
123
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mixed effect model in R with unstructured covariance [closed]
For the longitudinal data provided below, we have the following variables: the response variable y, the time variable 'week', 'grp' (with two levels: grp1 and grp2), and 'subject'. My objective is to ...
- 1,183
0
votes
1
answer
30
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Additional covariate reduces AIC in mixed models (LMM, GLMM, GAM)
In repeated measure for timepoints in different Group, Age and Gender act as a covariate in ...
- 69.5k
6
votes
2
answers
217
views
exclude random effects component for a repeated measure
I'm analyzing a dataset on the Nurse Licensure Exam, comprising 3000 participants. (n)
These 3000 participants were randomly recruited from 13 Sites across the US. (group level variable)
About 40% of ...
- 28.3k
1
vote
0
answers
37
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How to specify mixed-effects using lme4 in r for a within-subjects experiment [closed]
Now I want to regress the overall quality of the ideas (DV) on the source interacting with a continuous variable. I was advised to use the lme4 package, but I am ...
- 11
2
votes
1
answer
98
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Mixed model that tests for within-subject differences between two conditions while including covariates
I would like to use a mixed model to test if the values in a response variable differ between two conditions that each subject underwent. On top, I would like to control for the influence of other ...
- 10.7k
3
votes
2
answers
823
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nlme estimates near zero variance for the random effects
I am doing various analysis on a small sample. Basically, we have an experiment where 14 subjects (UID 1 ~ 14) used one of the 6 machines (MID 1 ~ 6) on 3 occasions (Sequence 1 ~ 3). Each time an ...
- 2,391
6
votes
1
answer
137
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Modeling repeated measures data in R - Interpretation and Validation
I am currently working on a control-case study where patients and controls are assessed at five different time intervals. The aim of the study is to assess possible differences in the response ...
- 5,890
0
votes
0
answers
1k
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Within and between group factor in linear mixed model?
Could I please get some advice on coding a linear mixed model for looking at between and within group effect.
I have 2 Timepoints (Baseline and 12 weeks Post intervention) and 2 groups (Ex1 and Ex2).
<...
CommunityBot
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1
vote
1
answer
585
views
Can lme4 fit a repeated measures model with unstructured covariance? How does it differ from fitting using gls in nlme?
I recently read this paper by Donohue et al. in Pharmaceutical Statistics (Open access: https://doi.org/10.1002/pst.2285). Mixed model repeated measure (MMRM) analyses are discussed. In particular, ...
CommunityBot
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2
votes
0
answers
139
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Equivalence test with random effects
I am designing an experiment where I will test different subjects’ multiple times under two different conditions (lab and real life)
My hypothesis Is that that the subject will perform equivalent in ...
3
votes
1
answer
818
views
linear mixed effects models: should I aggregate repeated trials?
A colleague of mine asked me to analyse some data from a movement experiment.
Participants were asked to turn their head three times to the left (toL), three times to the right (toR), with both the ...
CommunityBot
- 1
2
votes
2
answers
97
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lmer analysis for 58 people 4 timepoints, advice on setting the model
I’m looking for some advice on analysing this data. I think I need a multilevel model.
I have 58 participants measured progesterone and a factor at 4 timepoints. I would like to do a model to see how ...
- 102k
4
votes
1
answer
40
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LMM for Repeated Measures tree ring chronology
Having my first go at R and stats.
I sampled and analyzed tree rings for different measures (width, density, etc.). There are 3 treatments, 3 plot per treatment, and 5 trees per plot. The ring time ...
- 65.9k
10
votes
2
answers
7k
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How can I test for differences in variation between groups in a mixed model (lme4)?
I would like to test for differences in variation, not in means, between two sites. By looking at a boxplot of my data I see that bird song in one site look much more variable in length than in ...
- 47.3k
1
vote
1
answer
42
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Physical model for multilocation RCBD with repeated measures in time
I am trying to write a model for an experimental design that looks like this:
There are 5 farms (A,B,C,D,E) , and each farm has a RCBD design with 2 treatments(1,2) randomized in 4 blocks in each farm....
- 82.8k
0
votes
1
answer
103
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Repeated-measures regression in single subject design
I'm grateful for advice on which R analysis to choose for the following study:
I measured stress in one subject on 27 days in the night and in the morning.
Now I want to predict stress in the night ...
- 2,769
1
vote
0
answers
47
views
How to conduct post hoc paired comparisons for mixed effects model?
I am working with some biological data where I am trying to compare 5 categories of genes by expression which occur at different loci (locations on the chromosomes). I have samples from different ...
- 255
10
votes
3
answers
655
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longitudinal data with unequal samples and end points
I've been asked to look at a dataset of repeated measures taken during exercise in participants under two conditions control and ...
- 21.5k
4
votes
1
answer
2k
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Repeated measures with nested data mixed effects model
Hi everyone: I'm hoping for help analyzing nested data in R.
I measured the mass of chicks at 3 time points; chicks were in one of two treatments (P and W) and in one of two environmental conditions (...
CommunityBot
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2
votes
1
answer
4k
views
How to build a Generalized Linear Mixed Model with repeated measures in R
I am trying to analyze a dataset where I have individuals from 3 different species (essentially 3 'treatments'), and I score each individual on a cognitive test once per day, for 10 days. Essentially, ...
- 47.3k
5
votes
2
answers
3k
views
lmer for repeated measures
I have several animal pairs pair. For each, I repeatedly measured daily proportions of time they spent in contact time.con (30-...
- 82.8k
1
vote
1
answer
183
views
linear mixed effect models: random intercept, no fixed intercept interpretation
I'm learning about linear mixed effect models and I'm having a hard time interpreting a repeated measures model that has a random intercept, but no fixed intercept.
As an example:
...
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0
votes
0
answers
54
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In multilevel modeling, the problem of no variability in lower-level units nested within the higher-level unit
Suppose that an observational study was conducted with 100 patients (i.e., 100 level-2 units). The researcher recorded whether a medical condition was present (coded as 1) or absent (coded as 0) in ...
- 101
7
votes
2
answers
4k
views
Maximal model for linear mixed-effects model for repeated mesaures design
I have a dataset of a psychological experiment with two within-subject factors. For simplicity, let's assume I'm collecting reaction time (RT) for the stimulus factors of color (red/blue/green) and ...
- 82.8k
1
vote
0
answers
44
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Mixed model development for repeated measures over 3 years
I have longitudinal data for multiple plant varieties, where plants were measured for their Performance at 10 time points (time) each year for 3 years.
Each variety (genotype) serves as a distinct ...
- 82.8k
2
votes
1
answer
2k
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R - Model specification for repeated measures in linear mixed-effect model (lmer)
I am quite new in linear mixed-effects models, and trying to figure out how to properly design my model according to what I want to show (especially with the nesting and random effect). I am reading ...
CommunityBot
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0
votes
0
answers
26
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Linear Mixed Model Looking for significant effects
Hello I'm currently doing data analysis of my study in R.
I'm having trouble with finding the right way to go about it though.
Snippet of my data:
...
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0
votes
0
answers
125
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Seeking Appropriate Mixed Effects Model for Covariance Structure in Grouped, Repeated Measures Data
I'm currently working on a project where I need to identify an appropriate model that accurately fits the data generation process of my study. The goal is to have a model in which the covariance ...
- 613
1
vote
0
answers
18
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add variable occurs between measurements LMM
I am interested in adding a variable to a repeated measurements model, LMM (3 measurements of QOL). But unlike gender, for example, which does not change between measurements, the variables I want to ...
2
votes
1
answer
170
views
Unstructured model vs random slope model for repeated measures based on R functions lmer, lme and gls
Here is the dataset for repeated measures:
...
- 102k
1
vote
1
answer
91
views
Mixed effects model to explore the linear relationship between two variables for each level of the repeated-measures in Rstudio using lme()
Background: I did an experiment in which 30 people watched 3 movie clips ("A", "B", and "C") in a random order. For each song and participant I measured one continuous ...
- 2,825
1
vote
2
answers
455
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Mixed model with two fixed effects, with repeated measures for only one of them
I am using linear mixed effect models to study the effect of a physical therapy treatment on two different populations of patients (Adolescents and Adults). The treatment is the same for both ...
- 216
2
votes
0
answers
68
views
How to deal with the rank deficiency in lmer for nested variable
Data and background of the study:
The data is a repeat measurement of metabolite levels in responses to 2 types of stimuli.
The data measured in 4 sessions— ...
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1
vote
1
answer
64
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Testing assumptions for repeated measures ANOVA
I was wondering how to assess residual normality of a repeated measures ANOVA. In some threads, users refer to Venables and Ripley: Residuals in multistratum analyses: Projections and recommend to ...
- 102k
7
votes
3
answers
618
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Repeated measures with single measurements
I have the following situation: General practitionar (gp), patient (pat) and consultation (cons).
Each gp has several patient and each patient can have 1 and more consultations with a specific ...
- 82.8k
0
votes
1
answer
74
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which LME model to use?
I am interested in learning whether a diet can help people lose weight. I randomly assigned participants to receive the new diet. Weight was monitored at baseline and again at the beginning of every ...
- 1,944
3
votes
1
answer
1k
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Mixed model with nlme accounting for autoregression, with multiple random effects
I have searched the web, found similar questions, but just not the same one. Here is my problem:
I am trying to analyse the effect of temperature range (T.range) on turtle activity (odba_mean).
I have ...
CommunityBot
- 1
2
votes
1
answer
74
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Repeated within family measurements in an lmer
I'm trying to model in R, how lizard head size (Continuous) can be predicted by mass (Continuous), hatch time (Factor: Early vs Late), and Clutch mass (Continuous), with Family as a random factor. An ...
- 102k
1
vote
0
answers
36
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lme4 subject-level random effect for repeated measures but subjects belong to two different groups reflecting fixed effect
I am analyzing effects for two different populations ('group membership') where each subject provided repeated measures. I would like to have the subject as a random effect given repeated measures, ...
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