CosmoMC: Parameter input option
Posted: November 07 2005
Hi,
This is regarding the temperature setting in the params.ini file. As I read from the readme file, "the temperature setting allows one to sample from P^(1/T) rather than P which is good for exploring the tails of distributions, discovering other local minima, and for getting more robust high-confidence error bars."
Could someone please elaborate more on this i.e. how does it exactly affect the likelihood values quantitatively. At present I am running cosmoMC with a new set of inflationary parameters for my model P(k) and evaluating the likelihoods keeping the temperature setting as 1 using both metropolis and slice sampling. I get reasonably good likelihood values. Increasing 'temperature' even slightly to say 1.1/1.05 improves the likelihood value. Increasing temperature further gives me an even lower Chi^2 minimum. How do I know where to stop (i.e. what value of temp shd I use) and whether I need to change the temperature setting at all for my case.
Is it more relevant for postprocessing?
Thanks.
Regards
Rita
This is regarding the temperature setting in the params.ini file. As I read from the readme file, "the temperature setting allows one to sample from P^(1/T) rather than P which is good for exploring the tails of distributions, discovering other local minima, and for getting more robust high-confidence error bars."
Could someone please elaborate more on this i.e. how does it exactly affect the likelihood values quantitatively. At present I am running cosmoMC with a new set of inflationary parameters for my model P(k) and evaluating the likelihoods keeping the temperature setting as 1 using both metropolis and slice sampling. I get reasonably good likelihood values. Increasing 'temperature' even slightly to say 1.1/1.05 improves the likelihood value. Increasing temperature further gives me an even lower Chi^2 minimum. How do I know where to stop (i.e. what value of temp shd I use) and whether I need to change the temperature setting at all for my case.
Is it more relevant for postprocessing?
Thanks.
Regards
Rita