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arXiv · 2002.03228

Intrinsic Dimension Estimation via Nearest Constrained Subspace Classifier

Liang Liao·Stephen John Maybank
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Abstract

We consider the problems of classification and intrinsic dimension estimation on image data. A new subspace based classifier is proposed for supervised classification or intrinsic dimension estimation. The distribution of the data in each class is modeled by a union of of a finite number ofaffine subspaces of the feature space. The affine subspaces have a common dimension, which is assumed to be much less than the dimension of the feature space. The subspaces are found using regression based on the L0-norm. The proposed method is a generalisation of classical NN (Nearest Neighbor), NFL (Nearest Feature Line) classifiers and has a close relationship to NS (Nearest Subspace) classifier. The proposed classifier with an accurately estimated dimension parameter generally outperforms its competitors in terms of classification accuracy. We also propose a fast version of the classifier using a neighborhood representation to reduce its computational complexity. Experiments on publicly available datasets corroborate these claims.

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Liang Liao, Stephen John Maybank. 2020-02-08. Intrinsic Dimension Estimation via Nearest Constrained Subspace Classifier. https://arxiv.org/abs/2002.03228

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