Questions tagged [nested-models]
One model is "nested" in another if it is a constrained version of it. Nested models can be compared with a likelihood-ratio test. Use this tag for questions about comparing non-nested models too.
186 questions
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Weighted quantile sum (WQS) and Cox model
I am working on weighted quantile sum (WQS), and I know that the WQS index obtained represents the effect of the mixture on my outcome.
In order to know which effect the mixture has on my outcome in ...
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Would a nested contrast work to look at the effects of a variable that has only some values specified and the rest are NA?
I have a dataframe where I'm studying the effects of a variable, say Word Type (with levels A,B,C,D) on reaction times (RTs). I have manually set treatment contrasts that compare each of these levels ...
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How to solve a binary logistic mixed effects model when there is unbalanced data and different variance structure with repeated measures?
Problem Description:
I want to fit a generalized linear mixed-effects model with a binary response (i.e., a Binary logistic mixed-effects model) where there are nested random effects, and each nested ...
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handling pseudoreplication in lmer, repeat measures over time that includes duplicate repeat measures
Wondered if you could help me out here on a common setup found in microbial data (measuring colony forming units, or CFU's).
In this synthetic dataset microbe containing samples are taken over time, ...
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Model(s) for paired and nested experiment
I am planning a field experiment consisting of reducing the population of a predator species to evaluate how this would affect the abundance of its prey species. As you can see in the image below, the ...
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Comparing nested models using bootstrap
I am working on my master thesis and have a dataset with multiple projects. The project type is defined by a categorical variable.
I am using two modeling approaches: linear regression and Random ...
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Significance testing from random slopes model
I'm trying to explore some operating characteristics of the random slopes model. In this context, we are thinking of a clinical trial with subjects randomized to one of two arms. I fit the below model ...
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Nested models and Hilbert space
Recently, in my GLM course, we analyzed linear regression from a more philosophical perspective using Hilbert spaces. My teacher suggests that we be careful when when two models are "nested.&...
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Simpler model has better fit
I am comparing two models, one of which is nested with respect the other. On occasions, the nested model (i.e. with fewer parameters) has a smaller RSS value (implying that it fits the data better, ...
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Why do I need a nested rather than two separate random effect(s) when accounting for pseudoreplication in the presence of repeated measurements?
I have a dataset from individuals, where measurements of different urinary biomarkers have been taken on two study visits:
Subject ID
Value
Visit
Biomarker
Predictors 1-10
1
1.2
1
A
1
1.4
2
A
1
1.5
1
...
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How to Handle a Dependent Variable in a Fractional Factorial Design of Experiments (DOE)?
I am designing a fractional factorial experiment with five quantitative variables. However, two of these variables are dependent on each other. Specifically:
One variable represents the amount of an ...
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How can I add a nested factor into aligned rank transformation model
I am trying to add in a nested factor of individual ID into my model using aligned rank transformation (from the R ARTool package) so I can run ANOVAs. So far I have not had much luck in getting ID ...
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Fitting separate LMMs for different interactions
I am analyzing longitudinal changes in a major clinical scale for depression symptoms (DV) using a linear mixed model (LMM). My full model included:
...
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Nested design with fixed and random effects: Is my R model correct?
I am trying to analyze a nested experimental design in R, but I am unsure whether I am approaching it correctly. I have a following data:
Set
Sample
Repet.
Response
1
1
1
y1
1
1
2
y2
1
2
1
y3
1
2
2
y4
...
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How to use mlogit for models where there are no choice specific variables
Suppose one wants to model choice of product among two cellphones and two colors, but cellphone 1 only comes in red or green while cellphone 2 only comes in blue or black. So there is a nesting in the ...
