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arXiv · 2110.10518

Online non-parametric change-point detection for heterogeneous data streams observed over graph nodes

Alejandro de la Concha·Argyris Kalogeratos·Nicolas Vayatis
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Abstract

Consider a heterogeneous data stream being generated by the nodes of a graph. The data stream is in essence composed by multiple streams, possibly of different nature that depends on each node. At a given moment $\tau$, a change-point occurs for a subset of nodes $C$, signifying the change in the probability distribution of their associated streams. In this paper we propose an online non-parametric method to infer $\tau$ based on the direct estimation of the likelihood-ratio between the post-change and the pre-change distribution associated with the data stream of each node. We propose a kernel-based method, under the hypothesis that connected nodes of the graph are expected to have similar likelihood-ratio estimates when there is no change-point. We demonstrate the quality of our method on synthetic experiments and real-world applications.

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Alejandro de la Concha, Argyris Kalogeratos, Nicolas Vayatis. 2021-10-20. Online non-parametric change-point detection for heterogeneous data streams observed over graph nodes. https://arxiv.org/abs/2110.10518

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