Convergence of the Markov chains is assessed by examination of the traces from the sampler. These are included for completeness for a number of runs in the results section.
The chains exhibited very high autocorrelations, which was a feature of the posterior distribution, and for this reason very many samples were taken. The autocorrelation within the chain was reduced by thinning the samples, and only using one in every 10. Consequently, the number of samples needed for the estimates in the results section was quite large indeed. After a number of exceedingly long run-times, it was decided to examine the sampling strategy more closely.