Fuzzy Twin Support Vector Machine Research Articles

A novel fuzzy twin support vector machine based on centered kernel alignment

A novel fuzzy twin support vector machine based on centered kernel alignment

A Fuzzy Twin Support Vector Machine Based on Dissimilarity Measure and Its Biomedical Applications

A Fuzzy Twin Support Vector Machine Based on Dissimilarity Measure and Its Biomedical Applications

Handling Multi-Class Problem by Intuitionistic Fuzzy Twin Support Vector Machines Based on Relative Density Information.

The intuitionistic fuzzy twin support vector machine (IFTSVM) merges the idea of the intuitionistic fuzzy set (IFS) with the twin support vector machine (TSVM), which can reduce the negative impact of noise and outliers. However, this technique is not suitable for multi-class and high-dimensional feature space problems. Furthermore, the computational complexity of IFTSVM is high because it uses the membership and non-membership functions to build a score function. We propose a new version of IFTSVM by using relative density in-formation. This idea approximates the probability density distribution in multi-dimensional continuous space by computing the K-nearest-neighbor distance of each training sample. Then, we evaluate all the training points by a one-versus-one-versus-rest strategy to construct the k-class classification hyperplanes. A coordinate descent system is utilized to reduce the computational complexity of the training. The bootstrap technique with a 95% confidence interval and Friedman test are conducted to quantify the significance of the performance improve-ments observed in numerical evaluations. Experiments on 24 bench-mark datasets demonstrate the proposed method produces promising results as compared with other support vector machine models reported in the literature.

Three-way imbalanced learning based on fuzzy twin SVM

Three-way decision (3WD) is a powerful tool for granular computing to deal with uncertain data, commonly used in information systems, decision-making, and medical care. Three-way decision gets much research in traditional rough set models. However, three-way decision is rarely combined with the currently popular field of machine learning to expand its research. In this paper, three-way decision is connected with SVM, a standard binary classification model in machine learning, for solving imbalanced classification problems that SVM needs to improve. A new three-way fuzzy membership function and a new fuzzy twin support vector machine with three-way membership (TWFTSVM) are proposed. The new three-way fuzzy membership function is defined to increase the certainty of uncertain data in both input space and feature space, which assigns higher fuzzy membership to minority samples compared with majority samples. To evaluate the effectiveness of the proposed model, comparative experiments are designed for forty-seven different datasets with varying imbalance ratios. In addition, datasets with different imbalance ratios are derived from the same dataset to further assess the proposed model’s performance. The results show that the proposed model significantly outperforms other traditional SVM-based methods.

Fuzzy twin support vector machine based on affinity and class probability for class imbalance learning

Fuzzy twin support vector machine based on affinity and class probability for class imbalance learning

Variational mode decomposition combined fuzzy-Twin support vector machine model with deep learning for solar photovoltaic power forecasting.

A novel Variational Mode Decomposition (VMD) combined Fuzzy-Twin Support Vector Machine Model with deep learning mechanism is devised in this research study to forecast the solar Photovoltaic (PV) output power in day ahead basis. The raw data from the solar PV farms are highly fluctuating and to extract the useful stable components VMD is employed. A novel Fuzzy–Twin Support Vector Machine (FTSVM) model developed acts as the forecasting model for predicting the solar PV output power for the considered solar farms. The twin support vector machine (SVM) model formulates two separating hyperplanes for predicting the output power and in this research study a fuzzy based membership function identifies most suitable two SVM prediction hyperplanes handling the uncertainties of solar farm data. For the developed, new VMD-FTSVM prediction technique, their optimal parameters for the training process are evaluated with the classic Ant Lion Optimizer (ALO) algorithm. The solar PV output power is predicted using the novel VMD-FTSVM model and during the process multi-kernel functions are utilized to devise the two fuzzy based hyperplanes that accurately performs the prediction operation. Deep learning (DL) based training of the FTSVM model is adopted so that the deep auto-encoder and decoder module enhances the accuracy rate. The proposed combined forecasting model, VMD-ALO-DLFTSVM is validated for superiority based on a two 250MW PV solar farm in India. Results prove that the proposed model outperforms the existing model in terms of the performance metrics evaluated and the forecasted PV Power.

Safe intuitionistic fuzzy twin support vector machine for semi-supervised learning

Learning unlabeled samples without deteriorating performance is a challenge in semi-supervised learning. In this paper, we propose a safe intuitionistic fuzzy twin support vector machine (SIFTSVM) for semi-supervised learning. In our SIFTSVM, whether an unlabeled sample should be learned by a twin support vector machine is determined by its plane intuitionistic fuzzy number. The unlabeled samples are learned gradually according to the current decision environment, which is safer and more precise than learning all of the unlabeled samples simultaneously. Interestingly, the iterative algorithm of our SIFTSVM obtains a solution to a mixed integer programming problem whose global solution corresponds to a classifier by learning the unlabeled samples with implicit labels. Experimental results on several synthetic datasets confirm the safety of our SIFTSVM for learning unlabeled samples, and the results on 56 groups of benchmark datasets demonstrate that our SIFTSVM outperforms the state-of-the-art semi-supervised classifiers on most groups.

Multi-category intuitionistic fuzzy twin support vector machines with an application to plant leaf recognition

The intuitionistic fuzzy twin support vector machine for multi-categorization is developed in this study, which incorporates both structural and empirical risk concepts. In this method, each training pattern is first aggregated with the appropriate membership and non-membership degrees, which describe the position of a pattern in relation to its class centre and surrounding circumstances in input or feature space, and then the separating hyperplane is constructed using the kernel function and convex quadratic programming. Empirical findings on an artificial and thirteen UCI standard datasets show that it outperforms well-known existing methods including improved support vector machines, K-nearest neighbour, logistic regression, decision trees, random forests, and multilayer perceptrons. Furthermore, the suggested classifier with linear, polynomial, and Gaussian kernels has been used to identify the leaves of various plants, where the shape, texture, and margin data are extracted from the leaf in order to categorize the plant species. The method’s generalization capacity is demonstrated by the classification results on two leaf datasets of thirty and one hundred species, respectively. To compare the suggested method’s prediction capacity with others, statistical analysis is performed using two non-parametric tests, Friedman and Wilcoxon, with a 5% threshold of significance. The results show that the proposed method yields better performance for both linear and non-linear kernels.

FTWSVM-SR: DNA-Binding Proteins Identification via Fuzzy Twin Support Vector Machines on Self-Representation.

Due to the high cost of DNA-binding proteins (DBPs) detection, many machine learning algorithms (ML) have been utilized to large-scale process and detect DBPs. The previous methods took no count of the processing of noise samples. In this study, a fuzzy twin support vector machine (FTWSVM) is employed to detect DBPs. First, multiple types of protein sequence features are formed into kernel matrices; Then, multiple kernel learning (MKL) algorithm is utilized to linear combine multiple kernels; next, self-representation-based membership function is utilized to estimate membership value (weight) of each training sample; finally, we feed the integrated kernel matrix and membership values into the FTWSVM-SR model for training and testing. On comparison with other predictive models, FTWSVM based on SR (FTWSVM-SR) obtains the best performance of Matthew's correlation coefficient (MCC): 0.7410 and 0.5909 on two independent testing sets (PDB186 and PDB2272 datasets), respectively. The results confirm that our method can be an effective DBPs detection tool. Before the biochemical experiment, our model can screen and analyze DBPs on a large scale.

Intuitionistic Fuzzy Laplacian Twin Support Vector Machine for Semi-supervised Classification

In general, data contain noises which come from faulty instruments, flawed measurements or faulty communication. Learning with data in the context of classification or regression is inevitably affected by noises in the data. In order to remove or greatly reduce the impact of noises, we introduce the ideas of fuzzy membership functions and the Laplacian twin support vector machine (Lap-TSVM). A formulation of the linear intuitionistic fuzzy Laplacian twin support vector machine (IFLap-TSVM) is presented. Moreover, we extend the linear IFLap-TSVM to the nonlinear case by kernel function. The proposed IFLap-TSVM resolves the negative impact of noises and outliers by using fuzzy membership functions and is a more accurate reasonable classifier by using the geometric distribution information of labeled data and unlabeled data based on manifold regularization. Experiments with constructed artificial datasets, several UCI benchmark datasets and MNIST dataset show that the IFLap-TSVM has better classification accuracy than other state-of-the-art twin support vector machine (TSVM), intuitionistic fuzzy twin support vector machine (IFTSVM) and Lap-TSVM.

Data-driven mechanism based on fuzzy Lagrangian twin parametric-margin support vector machine for biomedical data analysis

This paper proposes a fuzzy-based Lagrangian twin parametric-margin support vector machine (FLTPMSVM) to reduce the effect of the outliers presented in biomedical data. The proposed FLTPMSVM assigns the weights to each data sample on the basis of fuzzy membership values to reduce the effect of outliers. This paper also adopts the square of the 2-norm of slack variables to make the objective function more convex. The proposed FLTPMSVM solves simple linearly convergent iterative schemes instead of solving a pair of quadratic programming problems. No external toolbox is required for the proposed FLTPMSVM as compared to the other methods. To establish the applicability of the proposed FLTPMSVM in the area of biomedical data classification, numerical experiments are performed on several biomedical datasets. The proposed FLTPMSVM gives an improved generalization performance and reduced training cost as compared to support vector machine (SVM), twin support vector machine (TWSVM), fuzzy twin support vector machine (FTSVM), twin parametric-margin support vector machine (TPMSVM) and new fuzzy twin support vector machine (NFTSVM).

Predicting stock price trends based on financial news articles and using a novel twin support vector machine with fuzzy hyperplane

This study extracts the hidden topic model and emotional information from news articles. A novel fuzzy twin support vector machine is also developed to merge the large volume of information from on-line news, using this to predict stock price trends. Fuzzy set theory is very useful for this approach because the texts use fuzzy terminology, such as high/low and big/small, and the boundary between rising and falling categories is poorly defined. By using fuzzy partial ordering relation, the decision function of our approach is generalized such that the values assigned to the stocks fall within a specified range and indicate the membership grade of these stocks in the positive class (rising trends). The proposed approach is useful for dealing with outliers. Outliers only slightly increase the spread of the fuzzy decision boundary and the estimation of the mode of fuzzy hyperplane remains unchanged. Therefore, our model is more robust compared with other methods when the data contain some outliers. Besides, the membership grade estimated by the fuzzy decision boundary gives a better insight into the degree of confidence in the predicted outputs. The explicable characteristic for the degree of confidence is a vital aspect for decision-making applications.

A kernel fuzzy twin SVM model for early warning systems of extreme financial risks

AbstractIt is an important component of risk management in financial markets to develop an early warning systems (EWS) for extreme financial risk. In this paper, we establish a novel EWS called kernel fuzzy twin support vector machine (KFT‐SVM). Unlike T‐SVM, KFT‐SVM can deal with the noises and outliners in dataset and the fuzzy dataset with a lot of potential uncertain but important factors in financial markets by introducing the fuzzy approach. More importantly, the introduced kernel method can aid the fuzzy approach to achieve more valuable fuzzy memberships by transporting dataset from the input space to the kernel space and further improve the generalization performance of T‐SVM. Computational comparisons of KFT‐SVM against SVM, T‐SVM and FT‐SVM indicate the significant superiority of our proposed KFT‐SVM. Furthermore, we have investigated the favourable ability of KFT‐SVM for overcoming the class imbalance problem by comparison with that combined with the resampling method of the synthetic minority over‐sampling technique (SMOTE). The experimental result shows that our proposed KFT‐SVM can effectively overcome the class imbalance problem.

Intuitionistic Fuzzy Twin Support Vector Machines

Fuzzy twin support vector machine (FTSVM) is an effective machine learning technique that is able to overcome the negative impact of noise and outliers in tackling data classification problems. In the FTSVM, the degree of membership function in the sample space describes the space between input data and class center, while ignoring the position of input data in the feature space and simply miscalculated the ledge support vectors as noises. This paper presents an intuitionistic FTSVM (IFTSVM) that combines the idea of intuitionistic fuzzy number with twin support vector machine (TSVM). An adequate fuzzy membership is employed to reduce the noise created by the pollutant inputs. Two functions, i.e., linear and nonlinear, are used to formulate two nonparallel hyperplanes. An IFTSVM not only reduces the influence of noises, it also distinguishes the noises from the support vectors. Further, this modification can minimize a newly formulated structural risk and improve the classification accuracy. Two artificial and eleven benchmark problems are employed to evaluate the effectiveness of the proposed IFTSVM model. To quantify the results statistically, the bootstrap technique with the ${95\%}$ confidence intervals is used. The outcome shows that an IFTSVM is able to produce promising results as compared with those from the original support vector machine, fuzzy support vector machine, FTSVM, and other models reported in the literature.

Fuzzy Twin Support Vector Machine Based on Intra-class Hyperplane

Aiming at the sensitivity of twin support vector machines to noise and outliers, an improved fuzzy twin support vector machine is proposed. Aiming at the shortcomings of fuzzy membership based on the distance between a sample and its class center, this algorithm proposes a new fuzzy membership function that can effectively reflect sample uncertainty— based on intra-class hyperplane and sample affinity. When determining the membership function, the intra-class hyperplane replaces the class center, reducing the dependence on the sample set geometry and improving the model generalization ability. At the same time, considering the relation between each sample and the confusion degree of sample points, the sample affinity is applied to the design of membership function, so as to effectively distinguish the effective sample from noise and outliers and improve the classification accuracy. The experimental results show that compared with the twin support vector machine and the classic fuzzy support vector machine, the improved fuzzy twin support vector machine has better classification performance.

Entropy based fuzzy least squares twin support vector machine for class imbalance learning

In classification problems, the data samples belonging to different classes have different number of samples. Sometimes, the imbalance in the number of samples of each class is very high and the interest is to classify the samples belonging to the minority class. Support vector machine (SVM) is one of the widely used techniques for classification problems which have been applied for solving this problem by using fuzzy based approach. In this paper, motivated by the work of Fan et al. (Knowledge-Based Systems 115: 87–99 2017), we have proposed two efficient variants of entropy based fuzzy SVM (EFSVM). By considering the fuzzy membership value for each sample, we have proposed an entropy based fuzzy least squares support vector machine (EFLSSVM-CIL) and entropy based fuzzy least squares twin support vector machine (EFLSTWSVM-CIL) for class imbalanced datasets where fuzzy membership values are assigned based on entropy values of samples. It solves a system of linear equations as compared to the quadratic programming problem (QPP) as in EFSVM. The least square versions of the entropy based SVM are faster than EFSVM and give higher generalization performance which shows its applicability and efficiency. Experiments are performed on various real world class imbalanced datasets and compared the results of proposed methods with new fuzzy twin support vector machine for pattern classification (NFTWSVM), entropy based fuzzy support vector machine (EFSVM), fuzzy twin support vector machine (FTWSVM) and twin support vector machine (TWSVM) which clearly illustrate the superiority of the proposed EFLSTWSVM-CIL.

A fuzzy twin support vector machine based on information entropy for class imbalance learning

In real-world binary class datasets, the total number of samples may not be the same in both the classes, i.e. size of the majority class is much larger than minority class which is called as imbalance problem. In various classification problems, the main interest is to correctly classify the samples belonging to the minority class. Since support vector machine (SVM) and twin support vector machine (TWSVM) obtain the resultant classifier by giving same importance to all the training samples, it results in a biased classifier towards the majority class in imbalanced datasets. In this paper, by considering the fuzzy membership value for each sample, we have proposed an efficient approach, entropy-based fuzzy twin support vector machine for class imbalanced datasets (EFTWSVM-CIL) where fuzzy membership values are assigned based on the entropy values of samples. Here, we give more importance to the minority class by assigning relatively larger fuzzy memberships to the minority class samples. Further, it solves a pair of smaller-size quadratic programming problems (QPPs) rather than a large one as in the case of SVM. Experiments are performed on various real-world imbalanced datasets, and results of our proposed EFTWSVM-CIL are compared with twin support vector machine (TWSVM), fuzzy twin support vector machine (FTWSVM) and entropy-based fuzzy SVM (EFSVM) for imbalanced datasets.

A new fuzzy twin support vector machine for pattern classification

Fuzzy SVM is often used to solve the problem that patterns belonging to one class often play more significant roles in classification. In order to improve the efficiency and performance of fuzzy SVM, this paper proposes a new fuzzy twin support vector machine (NFTSVM) for binary classification, in which fuzzy neural networks and twin support vector machine (TWSVM) are incorporated. By design, the influence of the samples with high uncertainty can be mitigated by employing fuzzy membership to weigh the margin of each training sample, which improves the generalization ability. In addition, we show that the existing TWSVM and twin bounded support vector machines (TBSVM) are special cases of the proposed NFTSVM when the parameters of NFTSVM are appropriately selected. Moreover, the successive overrelaxation (SOR) technique is adopted to solve the quadratic programming problems (QPPs) in the proposed NFTSVM algorithm to speed up the training procedure. Experimental results obtained on several artificial and real-world datasets validate the feasibility and effectiveness of the proposed method.