Multinomial Sampling for Hierarchical Change-Point Detection
- URL: http://arxiv.org/abs/2007.12420v2
- Date: Tue, 3 Nov 2020 17:45:26 GMT
- Title: Multinomial Sampling for Hierarchical Change-Point Detection
- Authors: Lorena Romero-Medrano, Pablo Moreno-Mu\~noz and Antonio
Art\'es-Rodr\'iguez
- Abstract summary: We propose a multinomial sampling methodology that improves the detection rate and reduces the delay.
Our experiments show results that outperform the baseline method and we also provide an example oriented to a human behavior study.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Bayesian change-point detection, together with latent variable models, allows
to perform segmentation over high-dimensional time-series. We assume that
change-points lie on a lower-dimensional manifold where we aim to infer subsets
of discrete latent variables. For this model, full inference is computationally
unfeasible and pseudo-observations based on point-estimates are used instead.
However, if estimation is not certain enough, change-point detection gets
affected. To circumvent this problem, we propose a multinomial sampling
methodology that improves the detection rate and reduces the delay while
keeping complexity stable and inference analytically tractable. Our experiments
show results that outperform the baseline method and we also provide an example
oriented to a human behavior study.
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