R help - Jul 2020 - lme4 - Mixed Model question

Dear List, 

I?d appreciate any guidance on the following. 

I?m using a mixed effects logistic regression model, to allow coefficients to
vary by a group variable. However, my case is not typical in the sense that I
need to specify a different set of covariates for each level of the group
variable. Say I have 3 covariates {x1, x2, x3} and 2 groups {g1, g2}. I want to
specify a model for g1 that only depends on x1 and x2, and a model for g2 that
only depends on x2 and x3.

Is this possible with lme4?

Thanks,
Axel.

Dear Axel,

A few quick remarks.

1) This question is more suitable for r-sig-mixed-models.
2) A mixed model needs much more than two groups. If you have only a few
groups, consider a glm with group interactions.
3) Setting the value of a covariate to zero for a set of observations has
the same effect as setting its coefficient to zero for that set of
observations.

Best regards,

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 ma 13 jul. 2020 om 16:00 schreef Axel Urbiz <axel.urbiz at gmail.com>:
> Dear List,
>
> I?d appreciate any guidance on the following.
>
> I?m using a mixed effects logistic regression model, to allow coefficients
> to vary by a group variable. However, my case is not typical in the sense
> that I need to specify a different set of covariates for each level of the
> group variable. Say I have 3 covariates {x1, x2, x3} and 2 groups {g1, g2}.
> I want to specify a model for g1 that only depends on x1 and x2, and a
> model for g2 that only depends on x2 and x3.
>
> Is this possible with lme4?
>
> Thanks,
> Axel.
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
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> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
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