ARTICLE | doi:10.20944/preprints202110.0042.v1
Subject: Mathematics & Computer Science, Probability And Statistics Keywords: classification; ensemble; subspace; sparsity; feature ranking
Online: 4 October 2021 (10:36:37 CEST)
We propose a new ensemble classification algorithm, named Super Random Subspace Ensemble (Super RaSE), to tackle the sparse classification problem. The proposed algorithm is motivated by the Random Subspace Ensemble algorithm (RaSE). The RaSE method was shown to be a flexible framework that can be coupled with any existing base classification. However, the success of RaSE largely depends on the proper choice of the base classifier, which is unfortunately unknown to us. In this work, we show that Super RaSE avoids the need to choose a base classifier by randomly sampling a collection of classifiers together with the subspace. As a result, Super RaSE is more flexible and robust than RaSE. In addition to the vanilla Super RaSE, we also develop the iterative Super RaSE, which adaptively changes the base classifier distribution as well as the subspace distribution. We show the Super RaSE algorithm and its iterative version perform competitively for a wide range of simulated datasets and two real data examples. The new Super RaSE algorithm and its iterative version are implemented in a new version of the R package RaSEn.
ARTICLE | doi:10.20944/preprints202103.0767.v1
Subject: Mathematics & Computer Science, Algebra & Number Theory Keywords: Images; matrices; angles; subspace; linear algebra applications
Online: 31 March 2021 (12:42:31 CEST)
An image consisting of (m, n) pixels can be seen as a matrix of m × n size. Based on the formula of angles between two subspaces, a pair of angles can be defined between two matrices, by utilizing column spaces and row spaces of the two matrices. The singular values of each matrix can be used to calculate distances. Thus, a distance representation is obtained, and a pair of angles between 2 matrices of the same size.
ARTICLE | doi:10.20944/preprints202005.0451.v1
Subject: Mathematics & Computer Science, Applied Mathematics Keywords: Bilateral Line Local Binary Patterns; Facial matrix; Statistical subspace; Face recognition; Calibrated SVM model; Ensemble learning
Online: 27 May 2020 (12:07:19 CEST)
Local binary pattern is one of the visual descriptors and can be used as a powerful feature extractor for texture classification. In this paper, a novel representation for face recognition is proposed, called it Bilateral Line Local Binary Patterns (BL-LBP). This scheme is an extension of Line Local Binary Patterns descriptors in the statistical learning subspace. The present bilateral descriptors are fused with an ensemble learning of calibrated SVM models. The performance of this scheme is evaluated using 5 standard face databases. It is found that it is robust against illumination variation, diverse facial expressions and head pose variations and its recognition accuracy reaches 98 percent, running on a mobile device with a processing speed of 63 ms per face. Results suggest that our proposed method can be very useful for the vision systems that have limited resources where the computational cost is critical.