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arXiv · 1507.05339

Path-integral Evidence

T. D. Kitching·A. N. Taylor
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Abstract

Here we present a Bayesian formalism for the goodness-of-fit that is the evidence for a fixed functional form over the evidence for all functions that are a general perturbation about this form. This is done under the assumption that the statistical properties of the data can be modelled by a multivariate Gaussian distribution. We use this to show how one can optimise an experiment to find evidence for a fixed function over perturbations about this function. We apply this formalism to an illustrative problem of measuring perturbations in the dark energy equation of state about a cosmological constant.

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T. D. Kitching, A. N. Taylor. 2015-07-19. Path-integral Evidence. https://doi.org/10.1093/mnras%2Fstv1269

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