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Biological data generally contain complex and high-dimensional samples. In addition, the number of samples in biological datasets is much fewer than the number of features, so the vast number of features should be selected carefully and determine the optimal subset of features. Feature selection (FS) is a vital stage in biological data mining applications (e.g., classification) for dealing with the curse of dimensionality problems and finding highly informative features. This work proposes an effective FS approach based on a new version of Gray Wolf Optimizer (GWO) called Multi-strategy Gray Wolf Optimizer (MSGWO) for better features selection for biological data classification. The use of MSGWO in feature selection is to find the optimal subset of features between classes, solve premature convergence, and enhance the local search ability of the GWO algorithm. Multiple exploration and exploitation strategies are proposed to enhance the global search and local search abilities of the GWO algorithm through the optimization process. The support vector machine (SVM) classifier is used to evaluate the proposed GWO-based FS approaches. MSGWO was evaluated on thirteen high-dimensional biological datasets obtained from the UCI repository with a smaller number of instances. The reported results confirm that employing multiple exploration and multiple exploitation strategies is highly useful for enhancing the search tendency of the MSGWO in the FS domain. Statistical tests proved that the superiority of the proposed approach is statistically significant as compared to the basic GWO and similar wrapper-based FS techniques, including binary particle swarm optimization (BPSO), binary bat algorithm (BBA), binary gravitational search algorithm (BGSA), and binary whale optimization algorithm (BWOA). In terms of classification accuracy, MSGWO yielded better accuracy rates than the standard GWO algorithm on 84% of applied biological datasets. MSGWO also recorded better accuracy rates than its other competitors in all 13 cases. In terms of the lowest number of selected features, MSGWO yielded excellent reduction rates compared to its peers. [ABSTRACT FROM AUTHOR]

Data classification is a challenging problem. Data classification is very sensitive to the noise and high dimensionality of the data. Being able to reduce the model complexity can help to improve the accuracy of the classification model performance. Therefore, in this research, we propose a novel feature selection technique based on Binary Harris Hawks Optimizer with Time-Varying Scheme (BHHO-TVS). The proposed BHHO-TVS adopts a time-varying transfer function that is applied to leverage the influence of the location vector to balance the exploration and exploitation power of the HHO. Eighteen well-known datasets provided by the UCI repository were utilized to show the significance of the proposed approach. The reported results show that BHHO-TVS outperforms BHHO with traditional binarization schemes as well as other binary feature selection methods such as binary gravitational search algorithm (BGSA), binary particle swarm optimization (BPSO), binary bat algorithm (BBA), binary whale optimization algorithm (BWOA), and binary salp swarm algorithm (BSSA). Compared with other similar feature selection approaches introduced in previous studies, the proposed method achieves the best accuracy rates on 67% of datasets. [ABSTRACT FROM AUTHOR]

In the feature selection process, reaching the best subset of features is considered a difficult task. To deal with the complexity associated with this problem, a sophisticated and robust optimization approach is needed. This paper proposes an efficient feature selection approach based on a Boolean variant of Particle Swarm Optimization (BPSO) boosted with Evolutionary Population Dynamics (EPD). The proposed improvement assists the BPSO to avoid local optima obstacles via boosting its exploration ability. In the BPSO-EPD, the worst half of the solutions are discarded by repositioning them around the optimal solutions selected from the best half. Six natural selection mechanisms comprising Best-based, Tournament, Roulette wheel, Stochastic universal sampling, Linear rank, and Random-based are employed to select guiding solutions. To assess the performance of the proposed improvement, 22 well-regarded datasets collected from the UCI repository are employed. The experimental results demonstrate the superiority of the proposed EPD-based feature selection approaches, especially the BPSO-TEPD variant when compared with conventional BPSO and other five EPD-based variants. Taking SpecEW dataset as an example, an increment of 6.7% accuracy can be achieved for BSPO-TEPD. Consequently, BPSO-TEPD approach also outperformed other well-known optimizers, including two binary variants of PSO using S-shaped transfer function (SBPSO) and V-shaped transfer function (VBPSO), Binary Grasshopper Optimization Algorithm (BGOA), Binary Gravitational Search Algorithm (BGSA), Binary Ant Lion Optimizer (BALO), Binary Bat algorithm (BBA), Binary Salp Swarm Algorithm (BSSA), Binary Whale Optimization Algorithm (BWOA), and Binary Teaching-Learning Based Optimization (BTLBO). The result emphasizes the excellent behavior of EPD strategies in evolving the ability of BPSO when dealing with feature selection problems. • Boolean PSO is used to propose a feature selection method. • Various EPD mechanisms have integrated with the BPSO to enhance its search power. • The BPSO-TEPD method has better performance when compared with nine optimizers. • The BPSO-TEPD perceives the highest accuracy in 16 out of 22 datasets. [ABSTRACT FROM AUTHOR]