Truncated Harmonic Mean Estimator of the Marginal Likelihood for Block Models // Implements the truncated harmonic mean estimator (THAMES) and other estimators of the reciprocal marginal likelihood for block models. This is done via reciprocal importance sampling, using posterior samples and unnormalized log posterior values. For further information see Metodiev, Perrot-Docks, Fouetilou, Latouche Raftery (2026).