I attended Topic 7 Multilevel Modeling with latent variables using M-Plus workshop at Johns Hopkins, I have a little question on slide pp141 of your presentation. The categorical variables are u1-u6, they were treated as categorical factor indicators on the WITHIN level. However, on the between level, they were continuous latent variable. May I know why is that so? Appreciate if you could advise. Also where could I find the example data sets used in the presentation?