All Questions
Tagged with model-selection generalized-linear-model
77
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Questions regarding the definition of the deviance in the context of GLMs
I've been self-studying GLMs and I have some questions regarding the deviance in the context of GLMs. In Generalized Additive Models An Introduction with R, the author defines the deviance of a model ...
- 21
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78
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How can Null model likelihood be higher than Fitted model likelihood
As far as I know, when fitting a GLM, the fitted model should always have a higher likelihood compared to the null model (with only an intercept) for the same training set. When I run a small ...
- 1,355
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69
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Understanding LOO / WAIC for Bayesian models selection
I'm trying to select between two models. 1. has a Truncated Normal likelihood and 2. has a Gamma likelihood. 1. has a much higher WAIC/LOO score but the posterior predictive in 2. (specifically the ...
- 211
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Multiple vs Single Predictor Variables for GLMM Pairwise Comparisons
I am running binomial GLMMs in R to determine whether species presence (binary) on a hydrophone is different between seasons (i.e. spring, summer, fall, and winter) and photoperiods (i.e. day, night, ...
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Model selection for robust linear regression methods
I have fitted respectively a zero-knot, a one-knot and a two-knot linear spline to my data, and I need some index of model performance for model selection. The crucial point is that the splines are ...
- 125
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Is it possible that GEE and mixed effect GLM give contradicting answers? If so, which one should be trusted?
Is it possible that GEE and mixed effect GLM give contradictive answers in significance of covariates? I assume both GEE and GLM selects same covariates. If so, which one should be trusted?
From ...
- 1,445
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275
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Univariate vs multivariate GLMs for inferring covariate-response relationships with no interactions
I understand that multivariate GLMs/multiple regression are valuable for predicting responses for observations with multiple covariates and for inferring interactive effects of different combinations ...
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63
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Model comparison: what to do when reduced model doesn't converge?
This is a general question about how to do hypothesis testing via model comparison:
I want to test the significance of several different predictors in a data set using model comparison. After a lot of ...
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135
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Variable selection and interpretation of coefficients
I want to know the meaning of differences of effect sizes in the glm and interaction in R. For example, when I did as below,
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- 103
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2 groups - some participants are only in one group, some in both: how to analyze?
I want to compare questionnaire scores about symptom X arising from trigger Y vs. trigger Z. Usually I'd go for a between-subject design. However, some participants (~50% of the sample) have had X as ...
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2
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120
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Which choice model to analyse my binary stated choice experiment data to estimate willingess-to-pay?
I followed the recipe of a stated-choice experiment in political science https://doi.org/10.1093/pan/mpt024 (they call it "conjoint" but I think this term is debated).
In the end I made the ...
- 245
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Should I not include a predictor if it has a strong positive correlation with other predictors?
My predictor 'Waketime' has a correlation of 0.8 with my 2nd predictor 'Sleeptime' and a correlation of 0.3 with my 3rd predictor 'Bedtime'.
Should I not include this predictor in my analysis (a ...
- 41
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Can I compare lmer models with different fixed effects using anova
I know that this question sounds familiar to some other, but I believe the responses were not clear in those and were focused on REML models.
I would like to know if it is sensible to compare 2 or ...
- 221
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90
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Why is the residual deviance higher for the more complex model?
The residual deviance is higher for the more complex model. Why is this the case? Can I compare the residual deviance of a GLM and a multi-level model in this way or should I use something else ...
- 509
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Fitting glmms to data with very unbalanced sampling effort - could subsampling help?
I have a data set comprising measurements of invertebrate species richness from grab samples of seabed sediment collected from a shallow coastal area over a period of 20 years. The sampling effort is ...
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