Hi I have a general HMC question. I am repeating the results of a paper, which was able to resolve some very small parameter values along side much larger ones. One example is a group of parameters that ranges from 0.015 to 0.607. By all indications, the same prior was given to the whole group. In none of my experiments can I ever get such a wide range in my parameter values. The very fact I had to choose a large variance in the prior to cover the larger values, it forces all the smaller values to a comparable range also.
Does any one have any insight into how such relative precision can be achieved?