Page 1 of 1

Number of degrees of freedom in CosmoMC runs

Posted: December 16 2013
by Eyal Kazin
Hi all,

My apologies, if this is trivial to figure out, but I failed to find the number degrees of freedom used in my cosmoMc runs. I also could not find mention in the Planck XVI paper.

Is there any file that states the dof specifically (or number of data points, and parameters used so I could infer myself)?

I am currently running the October 2013 version. I am using the vanilla parameters (flat LCDM), with Planck+WP, without ACT or SPT.

If it is of importance to answer the question I use in the ini file:

DEFAULT(batch1/CAMspec_defaults.ini)
DEFAULT(batch1/lowl.ini)
DEFAULT(batch1/lowLike.ini)
DEFAULT(batch1/common_batch1.ini)

(apologies if I am missing any critical information, I am a new-be to cosmomc)

Re: Number of degrees of freedom in CosmoMC runs

Posted: December 16 2013
by Antony Lewis
The Planck likelihoods are not all normalized to match a chi-square value (e.g. low-L is actually negative), so I'm not sure it's a very well defined question/answer.

Number of degrees of freedom in CosmoMC runs

Posted: December 17 2013
by Eyal Kazin
Would it make sense, then, to do AIC (Akaike information criterion) and BIC (Bayesian information criterion) comparisons between results when using different data sets and adding parameters?
For BIC, e.g, I would need the number of data points used.

Where can I find the number of data points used for fitting Planck+WP including low-L?

Number of degrees of freedom in CosmoMC runs

Posted: March 27 2016
by Su GuanJhen
I encounter the same problem to find the degrees of freedom when using Planck data set. I tried to find the number of data points, but fail to find it in papers released by Planck.