Figure 1. Path Diagrams and brms R Code for Multidimensional Models.

The above plots contextualize the described models that utilized multidimensionality to account for violation of the local independence assumption along with the brms formula code used to fit the model for readers interested parsing the formulas. The figure in (a) shows the base unidimensional model that assumes no assumption violation. Figure (b) depicts the simple multidimensional model with each trial loading on a separate but correlated factor. Figure (c) corresponds to the latent change model. Finally, figure (d) is the growth model with loadings for all items within a trial shown.