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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.

Concurvity describes the nonlinear dependencies among predictor variables in an additive model, such as generalisaed additive models (GAMS; ). Concurvity is the nonlinear counterpart to "collinearity" in linear regresion models

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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 by concurvity are automatically dropped from my…
Marcel Gangwisch
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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) shows many of the variables have concurvity values…
EvaL
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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 concurvity in GAMs (here, here, and here), and a few on…
S. Robinson
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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 very high when i checked it. I read on GAM website…
putra panji
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concurvity in presence of random smooths

I am trying to fit a GAMM containing per subject random smooths using the bam function in mgcv as follows: peri.gam0 <- bam(global_intDTmc ~ s(time) + s(time,subject,bs="fs",m=1), data=pd_intdft, …
NAT
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GAM with the same variable in both fixed and random

I have a dataset collected over multiple years, with many samples collected per year. The samples are assumed be random within year (collected over a short period of time, over a large area, in a randomized spatial design). I want to assess the…
user2602640
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High concurvity with random effect terms in generalized additive mixed effects models GAMM

I have a quick question concerning concurvity in a generalized additive mixed effects model. There are wonderful aids for identifying concurvity for GAMs not containing random effects. However, I have not seen explanations concerning high concurvity…
drg19
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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 prop_spec vary with a further factor, bin_deg (4…
RMiller
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