Marcoulides, K.M. and Trinchera, L. 2024. A Novel Approach for Identifying Unobserved Heterogeneity in Longitudinal Growth Trajectories Using Natural Cubic Smoothing Splines. Journal of Behavioral Data Science. 4, 1 (May 2024), 1–18. DOI:https://doi.org/10.35566/jbds/marcoulides.