# Evaluating hetroskedasticity in a binomial residuals vs. fitted plot in glmer?

I am trying to validate the goodness of fit of a model in glmer using residuals plotting.

I went through many threads here related to this but still I am not sure that the solutions offered apply to my data.

The model I fitted is

m4<-glmer(match ~ Listgp + length + gender + age+ Listgp*gender + (Listgp-1|stimulus) + (length-1|listener), data = msba, family = "binomial", control=glmerControl(optCtrl=list(maxfun=20000)), nAGQ =1)

All variables in the model are categorical except for “age”. “Listgp” and “length” are my two variables of interest whereas “age” and “gender” are control variables.

Here is a simple plot of m4

Then I plotted a residual vs.fitted plot (using the Kerdeist package) and got the following plot (plot 2).

I then plotted the residuals against the three categorical variables that I have in the model.

Finally, I plotted the residuals against the continuous predictor (age) as follows.

Does the 2nd plot of predicted against residuals indicate that the model is a good fit of the data or not? And are my residuals heteroskedastic?

I read somewhere that the solid line has to overlay the dashed line in the center (0-line) of the predicted model- residuals plot but this is not what is happening in my glmer binomial model. Am I doing things correctly here?

Any help would be appreciated. Shad