jamovi

I am looking for some advice...

In terms of mixed effects modelling on GAMLj, how do you know whether to include a random slope in your model or just look at random intercepts?

Thanks

In general, you can try to put as random coefficients all the coefficients that may vary from cluster to cluster. If you find variability, you keep them in the random component, otherwise, you remove them. In other words, if an effect can be computed within each cluster, then it may be different from cluster to cluster, then it should be tested as random