ACCELERATING METROPOLIS–HASTINGS ALGORITHMS BY DELAYED ACCEPTANCE

Abstract

MCMC algorithms such as Metropolis–Hastings algorithms are slowed down by the computation of complex target distributions as exemplified by huge datasets. We offer a useful generalisation of the Delayed Acceptance approach, devised to reduce such computational costs by a simple and universal divide-and-conquer strategy. The generic acceleration stems from breaking the acceptance step into several parts, aiming at a major gain in computing time that out-ranks a corresponding reduction in acceptance probability. Each component is sequentially compared with a uniform variate, the first rejection terminating this iteration. We develop theoretical bounds for the variance of associated estimators against the standard Metropolis–Hastings and produce results on optimal scaling and general optimisation of the procedure.