Open Conference Systems, STATISTICS AND DATA SCIENCE: NEW CHALLENGES, NEW GENERATIONS

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Multiple testing of local maxima for detection of peaks on the (celestial) sphere.
Dan Cheng, Valentina Cammarota, Yabebal Fantaye, Domenico Marinucci, Armin Schwartzman

Last modified: 2017-05-22

Abstract


We present a topological multiple testing scheme for detecting peaks on the sphere un- der isotropic Gaussian noise, where tests are performed at local maxima of the observed field filtered by the spherical needlet transform. Our setting is different from the standard Euclidean/large same asymptotic framework, yet highly relevant to realistic experimental circumstances for some important areas of application in astronomy. More precisely, we shall focus on cases where a single realization of a smooth isotropic Gaussian random field on the sphere is observed, and a number of well-localized signals are superimposed on such background field. The proposed algorithms, combined with the Benjamini-Hochberg pro- cedure for thresholding p-values, provide asymptotic strong control of the False Discovery Rate (FDR) and power consistency as the signal strength and the frequency of the needlet transform get large. This novel multiple testing method can be applied, for instance, to point-source detection in Cosmic Microwave Background radiation (CMB) data.