Difference between revisions of "ForecastingStep1"

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*From Alessandro: I can reproduce the scatter in our results by slightly changing my parameter steps or going from  a 5 point to a 3 points formula for the derivatives. It seems intrinsic in the Fisher technique, At least for me the matrix inversion is very sensitive to small changes in its parameters in particular for those with strong degeneracies.
 
*From Alessandro: I can reproduce the scatter in our results by slightly changing my parameter steps or going from  a 5 point to a 3 points formula for the derivatives. It seems intrinsic in the Fisher technique, At least for me the matrix inversion is very sensitive to small changes in its parameters in particular for those with strong degeneracies.
 
*From Mat/Neelima: The choice of fiducials also seems to matter a bit.  For example, a small shift in fiducials gives about a ~10-15% change in the mnu error.
 
*From Mat/Neelima: The choice of fiducials also seems to matter a bit.  For example, a small shift in fiducials gives about a ~10-15% change in the mnu error.
*From Joel & Alex: Is it appropriate to do lmax(TE) = 5000 if we have lmax(TT) = 3000?  We have done this, but weren't sure of the reasoning here.
+
*From Joel & Alex: Is it appropriate to do lmax(TE) = 5000 if we have lmax(TT) = 3000?  We have done this, but weren't sure of the reasoning here. (Answer from Jo: we expect TT to be contaminated by extragalactic FG above about 3000, but TE doesn't have those foregrounds.)

Revision as of 04:40, 27 April 2016

Checking forecasting outputs

This should be run for the test case for S4+Planck. This is T/E/B/kappa. No clusters or BAO at this point (can be posted in other entries though). Settings described here and here:

  • S4 = single channel (e.g. 150 GHz) at 1 uK/amin in T and 1.4uK/amin in P, 3 arcmin resolution.
  • White noise, no FG inflation
  • S4 T/E/B/k over 40% of sky, 30<ell < lmax
  • Planck TT/TE/EE from 30<l<2500 over additional 20% of sky. Can use these 'Planck-pol' specs for noise:File:Planck pol.pdf
  • Planck TT at l<30 over 80% of sky
  • Tau prior 0.06+-0.01
  • lmax(TT)=3000 unless explicit foreground cleaning is done in code for kSZ etc
  • lmax(TE,EE)=5000 unless explicit foreground cleaning done in code
  • kk reconstructed from 30<l<lmax using MV estimate
  • quadratic estimator for lensing, ideally with iterative delensing
  • Gaussian likelihood neglecting T/E/k covariance is ok, but non-Gaussian better
  • non-linear power spectrum for kk, e.g. ok to use halofit in CAMB
  • if easy to do, use pivot k=0.05
  • don't need to use same fiducial, but useful to note what you have used.
Forecast parameters for LCDM (add columns if your code spits out different parameters e.g. h, sigma8)
obh2 och2 100 theta 10^9 As ns tau hubble
Stephen/Josquin 0.0222± 0.000022 0.1197±0.00053 -- 2.20±0.020 0.9655±0.0017 0.06±0.0052 67.74±0.20
Alex/Joel/Dan 0.022200±0.000029 0.1197±0.00059 -- 2.196±0.021 0.9655±0.0019 0.0600±0.0056 67.50±0.22
Mat/Neelima/Nam 0.0222±0.00003 0.1197±0.00058 -- 2.20±0.021 0.9655±0.0019 0.06±0.0056 67.31±0.22
Erminia/Jo/Danielle 0.0222±0.00003 0.1197±0.00062 1.0459±0.00009 2.20±0.021 0.9655±0.0020 0.06±0.0052
Cora/Kimmy 0.02225±0.00003 0.1198±0.00055 -- 2.207±0.019 0.9645±0.0018 0.06±0.0052 67.27±0.17
Renee/Doddy/Dan 0.02222±0.00003 0.1197±0.00064 -- 2.20±0.021 0.9655±0.0020 0.06±0.0058 69.0±0.25
Alessandro 0.02222±0.000028 0.1197±0.00057 -- 2.196±0.020 0.9655±0.0018 0.06±0.0055 67.5±0.21
Forecast parameters for LCDM+mnu (add columns if your code spits out different parameters e.g. h, sigma8)
obh2 och2 100 theta 10^9 As ns tau mnu (meV) hubble
Stephen/Josquin 0.0222± 0.000022 0.1197±0.00060 -- 2.20±0.035 0.9655±0.0019 0.06±0.0083 60±62 67.74±0.71
Alex/Joel/Dan 0.022200±0.000030 0.1197±0.00071 -- 2.196±0.039 0.9655±0.0022 0.0600±0.0089 60±75 67.50±0.88
Mat/Neelima/Nam 0.0222±0.00003 0.1197±0.00071 -- 2.20±0.039 0.9655±0.0020 0.06±0.0089 60±70 67.31±0.84
Erminia/Jo/Danielle 0.0222± 0.00003 0.1197±0.00077 1.046±0.00011 2.20±0.036 0.9655±0.0022 0.06±0.0084 60±68
Cora/Kimmy 0.02225±0.00003 0.1198±0.00065 -- 2.207±0.037 0.9645±0.0019 0.06±0.0086 58±64 67.27±0.73
Renee/Doddy/Dan 0.0222± 0.00003 0.1197±0.00077 -- 2.20±0.037 0.9655±0.0022 0.06±0.0086 60±71 69.0±0.85
Alessandro 0.0222± 0.000029 0.1197±0.0007 -- 2.196±0.036 0.9655±0.002 0.06±0.0086 60±64 67.5±0.78

Notes

  • From Jo: got these errors for Planck-alone for LCDM: 0.00017, 0.0014, 0.00047, 0.039, 0.004, 0.01.
  • From Alessandro: I can reproduce the scatter in our results by slightly changing my parameter steps or going from a 5 point to a 3 points formula for the derivatives. It seems intrinsic in the Fisher technique, At least for me the matrix inversion is very sensitive to small changes in its parameters in particular for those with strong degeneracies.
  • From Mat/Neelima: The choice of fiducials also seems to matter a bit. For example, a small shift in fiducials gives about a ~10-15% change in the mnu error.
  • From Joel & Alex: Is it appropriate to do lmax(TE) = 5000 if we have lmax(TT) = 3000? We have done this, but weren't sure of the reasoning here. (Answer from Jo: we expect TT to be contaminated by extragalactic FG above about 3000, but TE doesn't have those foregrounds.)