Non-Gaussianity and direction dependent systematics in HST key project data

Abstract

Two new statistics, namely ${\Delta }_{\chi }^2$ and ${\Delta }_{\chi }$, based on extreme value theory, were derived in \cite{gupta08,gupta10}. We use these statistics to study direction dependence in the HST key project data which provides the most precise measurement of the Hubble constant. We also study the non-Gaussianity in this data set using these statistics. Our results for ${\Delta }_{\chi }^2$ show that the significance of direction dependent systematics is restricted to well below one $\sigma$ confidence limit, however, presence of non-Gaussian features is subtle. On the other hand ${\Delta }_{\chi }$ statistic, which is more sensitive to direction dependence, shows direction dependence systematics to be at slightly higher confidence level, and the presence of non-Gaussian features at a level similar to the ${\Delta }_{\chi }^2$ statistic.

6 pages, 4 figures; accepted for publication in MNRAS

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• Is there Evidence for a Hubble bubble? The Nature of Type Ia Supernova Colors and Dust in External Galaxies
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Cited by in corpus (2)

• High-z Supernova Type Ia Data: non-Gaussianity and Direction Dependence
• Measurement of Hubble constant: Non-Gaussian Errors in HST key project data