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arXiv · 1111.1855

Fr\'echet means of curves for signal averaging and application to ECG data analysis

Jérémie Bigot
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Abstract

Signal averaging is the process that consists in computing a mean shape from a set of noisy signals. In the presence of geometric variability in time in the data, the usual Euclidean mean of the raw data yields a mean pattern that does not reflect the typical shape of the observed signals. In this setting, it is necessary to use alignment techniques for a precise synchronization of the signals, and then to average the aligned data to obtain a consistent mean shape. In this paper, we study the numerical performances of Fr\'echet means of curves which are extensions of the usual Euclidean mean to spaces endowed with non-Euclidean metrics. This yields a new algorithm for signal averaging without a reference template. We apply this approach to the estimation of a mean heart cycle from ECG records.

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Jérémie Bigot. 2011-11-08. Fr\'echet means of curves for signal averaging and application to ECG data analysis. https://arxiv.org/abs/1111.1855

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