We are trying to run Triadic APIM growth curve models using multilevel modeling. We have cortisol (cort) measurements across 4 time points for families of mothers, fathers, and children. We want to run a three-intercept APIM growth curve model to analyze the extent of interdependence from one time point to next across family members (lagged predictors of the outcome).
I want to confirm that the code and data structure we envision would work as intended. Expected R code to run: model