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arXiv · 1011.4996

Precise Estimation of Cosmological Parameters Using a More Accurate Likelihood Function

Masanori Sato·Kiyotomo Ichiki·Tsutomu T. Takeuchi
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Abstract

The estimation of cosmological parameters from a given data set requires a construction of a likelihood function which, in general, has a complicated functional form. We adopt a Gaussian copula and constructed a copula likelihood function for the convergence power spectrum from a weak lensing survey. We show that the parameter estimation based on the Gaussian likelihood erroneously introduces a systematic shift in the confidence region, in particular for a parameter of the dark energy equation of state w. Thus, the copula likelihood should be used in future cosmological observations.

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Masanori Sato, Kiyotomo Ichiki, Tsutomu T. Takeuchi. 2010-12-20. Precise Estimation of Cosmological Parameters Using a More Accurate Likelihood Function. https://doi.org/10.1103/physrevlett.105.251301

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