I have asked my share of stupid questions on this forum but don't let that discourage you from tackling the latest one.
Now cosmomc outputs -2 Ln(Like). For eg for lcdm I get 1769.36 (using only the wmap data, not CBI or ACBAR). But this number doesn't correspond to anything in the wmap3 paper. For eg. If I take the parameters I get from cosmomc for lcdm, generate the spectrum with camb and then use the wmap likelihood code directly using the 'test' program that's provided with the code I get the following:
The numbers here are close to the wmap3 paper, but clearly nothing like 1769 ! How does cosmomc compute this number? How many degrees of freedom does it use? Can someone please clarify this for me. For reference below are the lcdm parameters that gave the above likelihood.------------------------------------------------------------------
Breakdown of -2ln(L)
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MASTER TTTT = 1037.663329 for 970 ls
Beam/ptsrc TT correction = 1.888136
low l TTTT chi2 = 907.978652 for 957 pixels
low l TTTT det = -14.151686
MASTER TETE chi2 = 417.430196 for 427 ls
MASTER TETE det = 1.694096 TT/TE/EE/BB
lowl chi2 = 1183.418457 for 1172 pixels
TT/TE/EE/BB lowl det = 2.851461
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TOTAL -2ln(L) = 3538.772642
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Expected -2ln(L) = 3540.792945
Difference = -2.020303
Omega_b h^2 0.0223456
Omega_{DM} h^2 0.101281
Omega_{Lambda} 0.778772
z_{re} 12.0669
n_s 0.962249
10^{10} A_s 20.7481
H_0 74.7543
Age/GYr 13.6973
Omega_m 0.221228
tau 0.100327