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Dimension reduction is a crucial technique in machine learning and data mining, which is widely used in areas of medicine, bioinformatics and genetics. In this paper, we propose a two-stage local dimension reduction approach for classification on microarray data. In first stage, a new L1-regularized feature selection method is defined to remove irrelevant and redundant features and to select the important features (biomarkers). In the next stage, PLS-based feature extraction is implemented on the selected features to extract synthesis features that best reflect discriminating characteristics for classification. The suitability of the proposal is demonstrated in an empirical study done with ten widely used microarray datasets, and the results show its effectiveness and competitiveness compared with four state-of-the-art methods. The experimental results on St Jude dataset shows that our method can be effectively applied to microarray data analysis for subtype prediction and the discovery of gene coexpression., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Symbolic data are usually composed of some categorical variables used to represent discrete entities in many real-world applications. Mining of symbolic data is more difficult than numerical data due to the lack of inherent geometric properties of this type of data. In this paper, we use two kinds of kernel learning methods to create a kernel estimation model and a nonlinear classification algorithm for symbolic data. By using the kernel smoothing method, we construct a squared-error consistent probability estimator for symbolic data, followed by a new data transformation model proposed to embed symbolic data into Euclidean space. Based on the model, the inner product and distance measure between symbolic data objects are reformulated, allowing a new Support Vector Machine (SVM), called SVM-S, to be defined for nonlinear classification on symbolic data using the Mercer kernel learning method. The experiment results show that SVM can be much more effective for symbolic data classification based on our proposed model and measures. [ABSTRACT FROM AUTHOR]

The presence of complex distributions of samples concealed in high-dimensional, massive sample-size data challenges all of the current classification methods for data mining. Samples within a class usually do not uniformly fill a certain (sub)space but are individually concentrated in certain regions of diverse feature subspaces, revealing the class dispersion. Current classifiers applied to such complex data inherently suffer from either high complexity or weak classification ability, due to the imbalance between flexibility and generalization ability of the discriminant functions used by these classifiers. To address this concern, we propose a novel representation of discriminant functions in Bayesian inference, which allows multiple Bayesian decision boundaries per class, each in its individual subspace. For this purpose, we design a learning algorithm that incorporates the naive Bayes and feature weighting approaches into structural risk minimization to learn multiple Bayesian discriminant functions for each class, thus combining the simplicity and effectiveness of naive Bayes and the benefits of feature weighting in handling high-dimensional data. The proposed learning scheme affords a recursive algorithm for exploring class density distribution for Bayesian estimation, and an automated approach for selecting powerful discriminant functions while keeping the complexity of the classifier low. Experimental results on real-world data characterized by millions of samples and features demonstrate the promising performance of our approach. [ABSTRACT FROM AUTHOR]

Privacy is an important concern in the society, and it has been a fundamental issue when to analyze and publish data involving human individual's sensitive information. Recently, the slicing method has been popularly used for privacy preservation in data publishing, because of its potential for preserving more data utility than others such as the generalization and bucketization approaches. However, in this paper, we show that the slicing method has disclosure risks for some absolute facts, which would help the adversary to find invalid records in the sliced microdata table, resulting in breach of individual privacy. To increase the privacy of published data in the sliced tables, a new method called value swapping is proposed in this work, aimed at decreasing the attribute disclosure risk for the absolute facts and ensuring the l-diverse slicing. By value swapping, the published table contains no invalid information such that the adversary cannot breach the individual privacy. Experimental results also show that the NEW method is able to keep more data utility than the existing slicing methods in a published microdata table. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]