boundary (singular) fit for longitudinal data in 3dLMEr

AFNI Message Board
6

Since TwoAG is a mediator, you have two options:

  • Exclude TwoAG from the model; or
  • Center TwoAG within each session.

The difference between these approaches might be small. The reason for these options is briefly discussed in this blog post, and explained in more detail in this manuscript.

Does the variable Motion vary across sessions? Consider whether it is appropriate to include it as a covariate based on the provided material.

Gang Chen