Discriminant Analysis under <i>f</i>-Divergence Measures

In statistical inference, the information-theoretic performance limits can often be expressed in terms of a statistical divergence between the underlying statistical models (e.g., in binary hypothesis testing, the error probability is related to the total variation distance between the statistical m...

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Main Authors: Anmol Dwivedi, Sihui Wang, Ali Tajer
Format: Article
Language:English
Published: MDPI AG 2022-01-01
Series:Entropy
Subjects:
Online Access:https://www.mdpi.com/1099-4300/24/2/188
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author Anmol Dwivedi
Sihui Wang
Ali Tajer
author_facet Anmol Dwivedi
Sihui Wang
Ali Tajer
author_sort Anmol Dwivedi
collection DOAJ
description In statistical inference, the information-theoretic performance limits can often be expressed in terms of a statistical divergence between the underlying statistical models (e.g., in binary hypothesis testing, the error probability is related to the total variation distance between the statistical models). As the data dimension grows, computing the statistics involved in decision-making and the attendant performance limits (divergence measures) face complexity and stability challenges. Dimensionality reduction addresses these challenges at the expense of compromising the performance (the divergence reduces by the data-processing inequality). This paper considers linear dimensionality reduction such that the divergence between the models is maximally preserved. Specifically, this paper focuses on Gaussian models where we investigate discriminant analysis under five <i>f</i>-divergence measures (Kullback–Leibler, symmetrized Kullback–Leibler, Hellinger, total variation, and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mi>χ</mi><mn>2</mn></msup></semantics></math></inline-formula>). We characterize the optimal design of the linear transformation of the data onto a lower-dimensional subspace for zero-mean Gaussian models and employ numerical algorithms to find the design for general Gaussian models with non-zero means. There are two key observations for zero-mean Gaussian models. First, projections are not necessarily along the largest modes of the covariance matrix of the data, and, in some situations, they can even be along the smallest modes. Secondly, under specific regimes, the optimal design of subspace projection is identical under all the <i>f</i>-divergence measures considered, rendering a degree of universality to the design, independent of the inference problem of interest.
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spelling doaj.art-5f285c413ff74d2d8451add87546c2a32023-11-23T19:47:24ZengMDPI AGEntropy1099-43002022-01-0124218810.3390/e24020188Discriminant Analysis under <i>f</i>-Divergence MeasuresAnmol Dwivedi0Sihui Wang1Ali Tajer2Department of Electrical, Computer, and Systems Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USADepartment of Electrical, Computer, and Systems Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USADepartment of Electrical, Computer, and Systems Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USAIn statistical inference, the information-theoretic performance limits can often be expressed in terms of a statistical divergence between the underlying statistical models (e.g., in binary hypothesis testing, the error probability is related to the total variation distance between the statistical models). As the data dimension grows, computing the statistics involved in decision-making and the attendant performance limits (divergence measures) face complexity and stability challenges. Dimensionality reduction addresses these challenges at the expense of compromising the performance (the divergence reduces by the data-processing inequality). This paper considers linear dimensionality reduction such that the divergence between the models is maximally preserved. Specifically, this paper focuses on Gaussian models where we investigate discriminant analysis under five <i>f</i>-divergence measures (Kullback–Leibler, symmetrized Kullback–Leibler, Hellinger, total variation, and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mi>χ</mi><mn>2</mn></msup></semantics></math></inline-formula>). We characterize the optimal design of the linear transformation of the data onto a lower-dimensional subspace for zero-mean Gaussian models and employ numerical algorithms to find the design for general Gaussian models with non-zero means. There are two key observations for zero-mean Gaussian models. First, projections are not necessarily along the largest modes of the covariance matrix of the data, and, in some situations, they can even be along the smallest modes. Secondly, under specific regimes, the optimal design of subspace projection is identical under all the <i>f</i>-divergence measures considered, rendering a degree of universality to the design, independent of the inference problem of interest.https://www.mdpi.com/1099-4300/24/2/188dimensionality reductiondiscriminant analysis<i>f</i>-divergencestatistical inference
spellingShingle Anmol Dwivedi
Sihui Wang
Ali Tajer
Discriminant Analysis under <i>f</i>-Divergence Measures
Entropy
dimensionality reduction
discriminant analysis
<i>f</i>-divergence
statistical inference
title Discriminant Analysis under <i>f</i>-Divergence Measures
title_full Discriminant Analysis under <i>f</i>-Divergence Measures
title_fullStr Discriminant Analysis under <i>f</i>-Divergence Measures
title_full_unstemmed Discriminant Analysis under <i>f</i>-Divergence Measures
title_short Discriminant Analysis under <i>f</i>-Divergence Measures
title_sort discriminant analysis under i f i divergence measures
topic dimensionality reduction
discriminant analysis
<i>f</i>-divergence
statistical inference
url https://www.mdpi.com/1099-4300/24/2/188
work_keys_str_mv AT anmoldwivedi discriminantanalysisunderifidivergencemeasures
AT sihuiwang discriminantanalysisunderifidivergencemeasures
AT alitajer discriminantanalysisunderifidivergencemeasures