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arXiv · 2105.12618

Influence of the Bounds of the Hyperparameters on the Reconstruction of Hubble Constant with Gaussian Process

Wen Sun·Kang Jiao·Tong-Jie Zhang
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Abstract

The cosmological model-independent method Gaussian process (GP) has been widely used in the reconstruction of Hubble constant $H_0$, and the hyperparameters inside GP influence the reconstructed result derived from GP. Different hyperparameters inside GP are used in the constraint of $H_0$ derived from GP with observational Hubble parameter $H(z)$ data (OHD), and the influence of the hyperparameters inside GP on the reconstruction of $H_0$ with GP is discussed. The discussion about the hyperparameters inside GP and the forecasts for future data show that the consideration of the lower and upper bounds on the GP's hyperparameters are necessary in order to get an extrapolated result of $H_0$ from GP reliably and robustly.

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Wen Sun, Kang Jiao, Tong-Jie Zhang. 2021-05-26. Influence of the Bounds of the Hyperparameters on the Reconstruction of Hubble Constant with Gaussian Process. https://doi.org/10.3847/1538-4357%2Fac05b8

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