Questions tagged [mixed-model]
Mixed (aka multilevel or hierarchical) models are linear models that include both fixed effects and random effects. They are used to model longitudinal or nested data.
8,211 questions
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Which test do I use to estimate the preference of species?
I have a question about how to analyse my dataset and would really appreciate your advice.
My data consist of observations of a set of target plant species collected during field surveys. The surveys ...
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Modelling G x E interactions in linear and mixed models
I have performed two GWAS for a phenological trait over two year (one analysis for each year) and got different SNPs driving the trait each year. I want to assess whether there is a "year effect&...
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Inflation of p-values of likelihood-ratio tests in longitudinal data analysis, Part 2
This post is a follow‑up to my earlier question:
Inflation of p-values of likelihood-ratio tests in longitudinal data analysis.
We assume a parallel group design of two randomized groups where
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Mixed-effects modeling of ERP data: topographic factors, ROI selection, and circularity concerns
I'm analyzing ERP data (128 electrodes) with lmer in R and would appreciate your feedback on my modeling strategy. My experiment involves testing the interaction between two experimental factors (...
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Degrees of Freedom Question for mixed-design Experiment
I have an experiment with 1 between-subjects variable and 1 within-subjects variable. The between subjects variable is group and there are 2 groups. The within-subjects variable is design and has 2 ...
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Application of step function for time dependent covariates in coxme?
In one of my dissertation chapters, I am using survival analysis to assess time to next birth following calf loss in a wild dolphin population to address costs to female fitness. My question is about ...
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How to properly model repeat measurements within individuals, individuals sampled across two time scales (random effects?)
I'm trying to test whether a certain attribute of a species is predictive of a behavior. I have multiple repeat measurements of the behavior for a number of different individuals (unequal sample sizes)...
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How should data from multiple experiments with different panel sizes and demographics be handled?
I am working with historical sensory evaluation data and would appreciate advice on how to structure the data for machine learning modeling.
Over the past several years, our lab has conducted many ...
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Inflation of p-values of likelihood-ratio tests in longitudinal data analysis
I am interested in longitudinal data analysis, and I am concerned about
valid inference in mixed models.
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Predicted probabilities from a multilevel model with factor levels [closed]
I'm trying to predict probabilities from a zero-inflated count model using glmmTMB and running into issues with predicting new values to plot.
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Help with optimism-correction in bootstrapping on bivariate linear mixed effects model (conditional and marginal R2/calibration slope)
I’m new to statistical modelling, and I’ve managed to pick quite a complicated first problem.
Essentially, I have a bivariate linear mixed effects model, where I am trying to model an imaging ...
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Measuring differences between time-trajectories within-participant
I'm trying to plan an analysis for an experiment where the main question is regarding how the dependent variable changes over time in two conditions. The predicted difference is a difference between ...
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Coefficients in models [duplicate]
I have a situation where the beta of one of my variables (which is categorical) is greater than 1. I am not sure why, but my instinct is because the variable I am looking at is categorical.
Can anyone ...
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P-value adjustment for 3×3 interaction in LMM: MVT vs FDR
I am fitting a linear mixed model (lmer function in R) with a 3×3 factorial design (three fixed factors: a grouping factor with two levels; and 3-level and a 5-...
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Is an ordinal mixed model appropriate for my 2‑level repeated Likert outcome and 3‑group design?
I am analysing data from a study with the following design and would like feedback on whether an ordinal mixed model (e.g., clmm() from the ordinal package in R) is appropriate or whether I should opt ...
