[R-sig-ME] 4 binary DVs, subjects nested within schools
yvonnick.noel at free.fr
Wed Nov 23 09:57:40 CET 2011
> The data is like selections from a menu, where all of the above is
> possible. This actual project is about student behaviors in the class
> room, but it seems more understandable to me to think of it as a
> person's taste for ice cream. Respondents are asked "do you like
> chocolate ice cream" or "do you like vanilla ice cream" or "strawberry
> ice cream". So the dependent variable is multivariate like this (yes,
> no, yes, no).
> Where can I learn more about the multivariate approach to this?
> And why are multivariate approaches not making the same mistake that
> is described in this literature on comparison of coefficients across
> logit models fitted for separate groups. I mean, if the variance
> parameter is not identified, how can I meaningfully put together 4
> logit models?
What you need is a Rasch model (and by no means a multinomial model).
As to a mean of fitting this model with glmer, See:
Also, comparing slopes between groups is OK, but comparing slopes on a
multivariate response vector is less trivial. Item response models are
suited for that.
University of Brittany at Rennes
Department of Psychology
More information about the R-sig-mixed-models