Linked Questions
10 questions linked to/from Interpreting BLUPs or VarCorr estimates in mixed models?
62
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What is a difference between random effects-, fixed effects- and marginal model?
I am trying to expand my knowledge of statistics. I come from a physical sciences background with a "recipe based" approach to statistical testing, where we say is it continuous, is it normally ...
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14
votes
1
answer
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Interpretation of Fixed Effects from Mixed Effect Logistic Regression
I am confused by statements at a UCLA webpage about mixed effects logistic regression. They show a table of fixed effects coefficients from fitting such a model and the first paragraph belows seems to ...
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answer
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Marginal model versus random-effects model – how to choose between them? An advice for a layman
In searching for any info about marginal model and random-effects model, and how to choose between them, I have found some info but it was more-or-less mathematical abstract explanation (like for ...
9
votes
2
answers
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Conditional vs. Marginal models
I have data with an outcome of 0 or 1 (binary) representing success or failure. I also have two comparison groups (Treatment vs. Control). Each subject in the study contributed 2 observations (the ...
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1
answer
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Difference between marginal and conditional models
A marginal model accounts for the correlation within each cluster. A conditional model also takes into account the correlation within each cluster.
My questions are:
Does a marginal model models ...
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3
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2
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Random slope and intercept correlation. Not consistent in output vs manual calculation
Lets say individuals are nested within each ID and I am trying to a predict level 1 outcome Y from a level 1 predictor X with random slopes and intercepts. Using the nlme package in R, I ran the ...
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9
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2
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Why is the estimated variance of a random effect not equal to the variance of its BLUP estimates? [duplicate]
I am learning mixed effect model from here.
I built a simplified model and trying to extract the $\gamma$ vector from linear mixed effect model
$$y=X\beta+Z\gamma+\epsilon$$
then calculate ...
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3
votes
1
answer
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Subject specific vs population average predictions
I am in doubt whether in my thesis I should report on the subject specific predictions of the probability to respond with an 'I don't know' answer, or the population average. Consider for example the ...
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4
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2
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Covariance matrix for the random effect in mixed effects model
According to this post, matrix Omega and sigma are in the results of lmer when we fitting ...
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0
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Interpreting VarCorr estimates versus cor(ranef()) in lme4 mixed models
I am following-up this and this thread because I found it very difficult to understand the implications of using each of the two types of random-effect correlations. In particular, I fitted model like ...