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gamm shifting residuals in plots

2 messages · Vinicius Maia, Thierry Onkelinx

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Hi folks!

When running a gamm and seing its plots I found the residuals locations are shifted , I presume its because the gam smooth is fitted after  taking  the random effects into account (obviously). But I am not understanding how its possible to change data points location in these plots. The same is valid for the lmer, I usually plot the fitted line whith the residuals, but I have never seen this discrepancy in points positions with the fitted line before. I would appreciate if anyone could clarify what is happening.

Plots are attached

codes:

a) mod1=gamm(y1_r_prop~s(areia), random = list(area=~1,chave=~1),data=dadosest)
plot(mod1$gam,residuals=TRUE,pch=1.3,shift = coef(mod1$gam)[1])

b) mod2=gamm(y1_r_prop~s(areia), random = list(chave=~1),method="ML",data=dadosest)
plot(mod2$gam,residuals=TRUE,pch=1.3,shift = coef(mod2$gam)[1])

c) mod3=gamm(y1_r_prop~s(areia), random = list(area=~1),method="ML",data=dadosest)
plot(mod3$gam,residuals=TRUE,pch=1.3,shift = coef(mod3$gam)[1])

d) mod4=gam(y1_r_prop~s(areia),method="ML",data=dadosest)
plot(mod4,residuals=TRUE,pch=1.3,shift = coef(mod4)[1])

e) plot(y1_r_prop~areia)
curve(18.3048+-2.2142*x,add=TRUE) # coefficients from a lmer with both area and chave random effects

Thank you all!
#
The mailing accepts only a limited range of file extensions. Your images
got stripped from your mail. Put them somewhere online and send the link.
Sending a minimal reproducible example is better.

ir. Thierry Onkelinx
Statisticus / Statistician

Vlaamse Overheid / Government of Flanders
INSTITUUT VOOR NATUUR- EN BOSONDERZOEK / RESEARCH INSTITUTE FOR NATURE AND
FOREST
Team Biometrie & Kwaliteitszorg / Team Biometrics & Quality Assurance
thierry.onkelinx at inbo.be
Havenlaan 88 bus 73, 1000 Brussel
www.inbo.be

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Op vr 18 jan. 2019 om 02:11 schreef Vinicius Maia <
vinicius.a.maia at hotmail.com>: