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arXiv · 1311.0707

Generative Modelling for Unsupervised Score Calibration

Niko Brümmer·Daniel Garcia-Romero
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Abstract

Score calibration enables automatic speaker recognizers to make cost-effective accept / reject decisions. Traditional calibration requires supervised data, which is an expensive resource. We propose a 2-component GMM for unsupervised calibration and demonstrate good performance relative to a supervised baseline on NIST SRE'10 and SRE'12. A Bayesian analysis demonstrates that the uncertainty associated with the unsupervised calibration parameter estimates is surprisingly small.

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Niko Brümmer, Daniel Garcia-Romero. 2014-02-14. Generative Modelling for Unsupervised Score Calibration. https://arxiv.org/abs/1311.0707

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