pymc

Builds, fits, checks, and compares Bayesian models in Python with PyMC and ArviZ. Covers hierarchical (multilevel) models, NUTS MCMC sampling, variational inference (ADVI), prior and posterior predictive checks, convergence diagnostics (R-hat, ESS, divergences), and LOO/WAIC model comparison. Use when writing a PyMC model for regression, count, or binary data. Use when fitting a hierarchical model with partial pooling. Use when diagnosing divergences, low ESS, or high R-hat. Use when comparing candidate models with LOO. Use when choosing priors or running prior predictive checks. Not for non-Bayesian regression; use statsmodels or scikit-learn instead.

Version

1.4

License

Apache License, Version 2.0

Compatibility

Requires Python 3.12+ and PyMC 6.0.1-compatible dependencies. Install reproducible environments with `uv pip install "pymc[nutpie]==6.0.1"`; optional NumPyro or BlackJAX samplers require separately pinned JAX-compatible dependencies.