Questions tagged [concurvity]

Concurvity refers to the nonlinear dependencies among covariates in an additive model, and is related to the concept of collinearity among predictors in a linear model. This tag should be used when a question is related to (multi)collinearity in the predictors of a model where the model contains smooth functions of covariates such as generalized additive models.

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87 views

GAM: Do shrinkage smooth splines also address for concurvity?

I have a gam model with automatic predictor selection based on cubic splines (bs = cr) and SELECT == T or shrinkage cubic splines (bs = cs) and SELECT == F. Now I'm wondering if predictors affected ...
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0answers
43 views

Is it okay to ignore concurvity on our GAM model?

I'm trying to model a relationship between marine debris concentration (item/m^2) with several covariates using GAM with MGCV R package. I found that the concurvity values at worst-case scenario are ...
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0answers
31 views

GAM concurvity measures greater than 1

I am currently using a gam modelling approach to describe the effects of several variables (es_sum, nat_sum, sect_sum, and prop_spec) on another variable (btwn). Each of es_sum, nat_sum, sect_sum, and ...
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0answers
107 views

Variance components of a penalized spatial GAM have very large confidence intervals

I am working through a spatial GAM example in one of Simon Wood's lectures (found here), and ran into some problems surrounding concurvity and penalization. I've read a number of other posts on ...
1
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0answers
66 views

concurvity in presence of random smooths [closed]

I am trying to fit a GAMM containing per subject random smooths using the bam function in mgcv as follows: ...
4
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1answer
528 views

concurvity in negative binomial GAM

I'm using the concurvity function to check for concurvity in my model - a negative binomial GAM using the mgcv package in R. The output I get when comparing to the rest of the model (ie full=TRUE) ...