Is the Modified Harmonic Mean supposed to be much smaller than any actual log posterior values?

Hi all,

I’m trying to implement the Modified Harmonic Mean estimator from Geweke 1999 to estimate the marginal data density of a dsge model. The issue I’ve run into is that when I use the saved logposterior values (the likelihood times the prior) to calculate the MHME, I get a value that is substantially smaller than any actual log posterior values. Is this supposed to ever happen?

No, that is not supposed to happen.