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Optimal multiple change-point detection for high-dimensional data

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 نشر من قبل Emmanuel Pilliat
 تاريخ النشر 2020
  مجال البحث الاحصاء الرياضي
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 تأليف Emmanuel Pilliat




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This manuscript makes two contributions to the field of change-point detection. In a general change-point setting, we provide a generic algorithm for aggregating local homogeneity tests into an estimator of change-points in a time series. Interestingly, we establish that the error rates of the collection of test directly translate into detection properties of the change-point estimator. This generic scheme is then applied to the problem of possibly sparse multivariate mean change-point detection setting. When the noise is Gaussian, we derive minimax optimal rates that are adaptive to the unknown sparsity and to the distance between change-points. For sub-Gaussian noise, we introduce a variant that is optimal in almost all sparsity regimes.



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