BROOKS_GELMAN_STAT#
Name#
BROOKS_GELMAN_STAT
Purpose#
Computes the Brooks-Gelman statistic (i.e., the multivariate Gelman-Rubin statistic as given in Brooks & Gelman 1998) of multiple Markov chains. Uses the within-chain variance and between-chain variance for all parameters to compare convergence of the chains.
Calling Sequence#
r_hat = brooks_gelman_stat(chain)
Input#
chain
int, float, or double array(Nparam, Ntrials, Nparallel)An ensemble of Markov chains.
Output#
r_hat
double scalarThe Brooks-Gelman statistic of the chains. The \(\sqrt{\hat{R}}\) should be less than or equal to 1.2 if convergence of the chain was sufficiently reached.
References#
Modification History#
2020/06/10: Created (Keith Doore)
2022/07/14: Updated documentation and error handling (Keith Doore)