• Corpus ID: 244908442

Sidestepping the inversion of the weak-lensing covariance matrix with Approximate Bayesian Computation

  title={Sidestepping the inversion of the weak-lensing covariance matrix with Approximate Bayesian Computation},
  author={Martin Kilbinger and Emille E. O. Ishida and Jessi Cisewski-Kehe},
Weak gravitational lensing is one of the few direct methods to map the dark-matter distribution on large scales in the Universe, and to estimate cosmological parameters. We study a Bayesian inference problem where the data covariance C, estimated from a number ns of numerical simulations, is singular. In a cosmological context of large-scale structure observations, the creation of a large number of suchN -body simulations is often prohibitively expensive. Inference based on a likelihood… 

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