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title author date bibliography
MCMC notes
Ben Bolker
6 October 2021
mcmc.bib

This is a very broad outline/brain dump.

Basic ideas

[@gilks_markov_1995; @van_ravenzwaaij_simple_2018; @bolker_ecological_2008]

  • need to construct a Markov chain on the parameter space
  • stationarity, ergodicity, irreducibility
  • detailed balance/reversibility: $\pi_i P_{ij} = \pi_j P_{ji}$

Sampling strategies

  • Metropolis-Hastings
  • Gibbs (conditional conjugate sampling)
  • slice
  • 'generalized Gibbs' (x-within-Gibbs)
  • hybrid/Hamiltonian MCMC (uses gradient info)
  • reversible-jump MCMC (variable dimensionality)
  • sequential MC (time series etc.)
  • Metropolis-coupled MCMC (MC^3) (tempering) [@altekar_parallel_2004]

Platforms

  • BUGS/JAGS
  • Stan (+ rethinking::ulam)
  • Nimble
  • PyMC3
  • TMB + tmbstan
  • greta
  • special-case front ends (MCMCglmm, brms, rstanarm, ...)

(1) Which samplers are available? (2) Simplicity vs flexiblity (2) Procedural or graphical model definition?

Diagnostics and visualization

  • trace plots
  • R-hat, improved R-hat, effective sample size, ... [@vehtari_rank-normalization_2019; @lambert_r_2020]
  • simulation-based calibration [@talts_validating_2020]

Troubleshooting

  • tuning/adaptation [@rosenthal_optimal_2011]
    • shape of candidate distribution should match shape of posterior
    • acceptance probability 0.1 to 0.6, approx 0.24 in high dim
  • change samplers
  • reparameterize
  • make priors stronger
  • run longer!

See @gelman_bayesian_2020

More resources

  • @betancourt_markov_2020: long blog post with geometry, examples, etc.; semi-technical
  • @kery_introduction_2010: what it sounds like. Various standard models implemented and explained in WinBUGS
  • @kery_bayesian_2011: as previous, but focusing on models for ecologists; state-space models for population counts, capture-mark-recapture data, occupancy models, etc.
  • @liang_advanced_2010: haven't read it but looks interesting??

References