174,436 research outputs found
Adaptation of speaker-specific bases in non-negative matrix factorization for single channel speech-music separation
This paper introduces a speaker adaptation algorithm for nonnegative matrix factorization (NMF) models. The proposed adaptation algorithm is a combination of Bayesian and subspace model adaptation. The adapted model is used to separate speech signal from a background music signal in a single record. Training speech data for multiple speakers is used with NMF to train a set of basis vectors as a general model for speech signals. The probabilistic interpretation of NMF is used to achieve Bayesian adaptation to adjust the general model with respect to the actual properties of the speech signals that is observed in the mixed signal. The Bayesian adapted model is adapted again by a linear transform, which changes the subspace that the Bayesian adapted model spans to better match the speech signal that is in the mixed signal. The experimental results show that combining Bayesian with linear transform adaptation improves the separation results
Statistical methods for linguistic research: Foundational Ideas - Part II
We provide an introductory review of Bayesian data analytical methods, with a
focus on applications for linguistics, psychology, psycholinguistics, and
cognitive science. The empirically oriented researcher will benefit from making
Bayesian methods part of their statistical toolkit due to the many advantages
of this framework, among them easier interpretation of results relative to
research hypotheses, and flexible model specification. We present an informal
introduction to the foundational ideas behind Bayesian data analysis, using, as
an example, a linear mixed models analysis of data from a typical
psycholinguistics experiment. We discuss hypothesis testing using the Bayes
factor, and model selection using cross-validation. We close with some examples
illustrating the flexibility of model specification in the Bayesian framework.
Suggestions for further reading are also provided.Comment: 30 pages, 5 figures, 4 tables. Submitted to Language and Linguistics
Compass. Comments and suggestions for improvement most welcom
Bayesian Model Comparison in Genetic Association Analysis: Linear Mixed Modeling and SNP Set Testing
We consider the problems of hypothesis testing and model comparison under a
flexible Bayesian linear regression model whose formulation is closely
connected with the linear mixed effect model and the parametric models for SNP
set analysis in genetic association studies. We derive a class of analytic
approximate Bayes factors and illustrate their connections with a variety of
frequentist test statistics, including the Wald statistic and the variance
component score statistic. Taking advantage of Bayesian model averaging and
hierarchical modeling, we demonstrate some distinct advantages and
flexibilities in the approaches utilizing the derived Bayes factors in the
context of genetic association studies. We demonstrate our proposed methods
using real or simulated numerical examples in applications of single SNP
association testing, multi-locus fine-mapping and SNP set association testing
Generalized fiducial inference for normal linear mixed models
While linear mixed modeling methods are foundational concepts introduced in
any statistical education, adequate general methods for interval estimation
involving models with more than a few variance components are lacking,
especially in the unbalanced setting. Generalized fiducial inference provides a
possible framework that accommodates this absence of methodology. Under the
fabric of generalized fiducial inference along with sequential Monte Carlo
methods, we present an approach for interval estimation for both balanced and
unbalanced Gaussian linear mixed models. We compare the proposed method to
classical and Bayesian results in the literature in a simulation study of
two-fold nested models and two-factor crossed designs with an interaction term.
The proposed method is found to be competitive or better when evaluated based
on frequentist criteria of empirical coverage and average length of confidence
intervals for small sample sizes. A MATLAB implementation of the proposed
algorithm is available from the authors.Comment: Published in at http://dx.doi.org/10.1214/12-AOS1030 the Annals of
Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical
Statistics (http://www.imstat.org
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