flexBART - A More Flexible BART Model
Implements a faster and more expressive version of
Bayesian Additive Regression Trees that, at a high level,
approximates unknown functions as a weighted sum of binary
regression tree ensembles. Supports fitting (generalized)
linear varying coefficient models that posits a linear
relationship between the inverse link and some covariates but
allows that relationship to change as a function of other
covariates. Additionally supports fitting heteroscedastic BART
models, in which both the mean and log-variance are
approximated with separate regression tree ensembles. A formula
interface allows for different splitting variables to be used
in each ensemble. For more details see Deshpande (2025)
<doi:10.1080/10618600.2024.2431072> and Deshpande et al. (2026)
<doi:10.1214/24-BA1470>.