/!\ Working version, still under development. Please report any bug to arthur.chatton(at)umontreal.ca
R package of the Positivity regression trees algorithm for checking the causal assumption of positivity.
See Danelian et al. (2023) for cross-sectional studies and Chatton et al. (2025) for longitudinal studies.
No examples are currently provided in the documentation, but a notebook with simulated data is available at https://github.com/ArthurChatton/sPoRT-notebook.
Chatton, A., Schomaker, M., Luque-Fernandez, M.-A., Platt, R. W., & Schnitzer, M. E. (2025). Is Checking for Sequential Positivity Violations Getting You Down? Try sPoRT! Epidemiology, in press. Doi: 10.1097/EDE.0000000000001902
Danelian, G., Foucher, Y., Léger, M., Le Borgne, F., & Chatton, A. (2023). Identification of in-sample positivity violations using regression trees: The PoRT algorithm. Journal of Causal Inference, 11(1), 20220032. Doi: 10.1515/jci-2022-0032