Cosmological parameter estimation via iterative emulation of likelihoods

  title={Cosmological parameter estimation via iterative emulation of likelihoods},
  author={Marcos Pellejero-Iba{\~n}ez and Raul E Angulo and Giovanni Aric{\'o} and Matteo Zennaro and Sergio Contreras and Jens St{\"u}cker},
  journal={arXiv: Cosmology and Nongalactic Astrophysics},
The interpretation of cosmological observables requires the use of increasingly sophisticated theoretical models. Since these models are becoming computationally very expensive and display non-trivial uncertainties, the use of standard Bayesian algorithms for cosmological inferences, such as MCMC, might become inadequate. Here, we propose a new approach to parameter estimation based on an iterative Gaussian emulation of the target likelihood function. This requires a minimal number of… Expand

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