English

A note on Bayesian R-squared for generalized additive mixed models

Methodology 2024-10-21 v1

Abstract

We present a novel Bayesian framework to decompose the posterior predictive variance in a fitted Generalized Additive Mixed Model (GAMM) into explained and unexplained components. This decomposition enables a rigorous definition of Bayesian R2R^{2}. We show that the new definition aligns with the intuitive Bayesian R2R^{2} proposed by Gelman, Goodrich, Gabry, and Vehtari (2019) [\emph{The American Statistician}, \textbf{73}(3), 307-309], but extends its applicability to a broader class of models. Furthermore, we introduce a partial Bayesian R2R^{2} to quantify the contribution of individual model terms to the explained variation in the posterior predictions

Keywords

Cite

@article{arxiv.2410.14002,
  title  = {A note on Bayesian R-squared for generalized additive mixed models},
  author = {Abdollah Jalilian and Aki Vehtari and Luigi Sedda},
  journal= {arXiv preprint arXiv:2410.14002},
  year   = {2024}
}
R2 v1 2026-06-28T19:26:34.691Z