A Survey on Feature Selection Techniques for Predictive Analytics
The feature selection is a crucial step in predictive analytics to determine which subset of features makes the most contribution to the high-dimensional data and remove irrelevant, redundant, or noisy features. The dimensionality of datasets keeps on growing, and, as contemporary data-driven applications produce large volumes of heterogeneous data, overfitting, computational complexity, worse model interpretability, and poorer generalization become issues as heterogeneous data increases. The feature selection methods are meant to address such challenges by improving predictive accuracy, minimizing training time and improving model robustness. This survey is a systematic and extensive overview of feature selection methods used in predictive analytics which are utilized in a variety of areas and fields, including healthcare, finance, bioinformatics, cybersecurity, and smart systems. In the paper, the features selection techniques have been classified as filter, wrapper, embedded, and hybrid techniques which give a comprehensive theoretical background of each of the techniques as well as a comparison of each of the techniques. Statistical, information-theoretic, similarity-based, and probabilistic filters are discussed in addition to the heuristic and metaheuristic wrapper methods, i.e. evolutionary, swarm-based etc. Also critically analyzed is embedded techniques that make use of regularization, decision trees, and ensemble learning. Moreover, this survey talks about the evaluation metrics, benchmark data, and design considerations of the experiment which are used in the evaluation of the effectiveness of the feature selection. Such practice issues as scalability, stability, data imbalance, and interpretability are mentioned, as well as new directions related to deep learning-based feature selection and multi-objective optimization and explainable artificial intelligence. This piece of work can be regarded as a useful source of information by the researcher and practitioners who want to develop effective, precise, and understandable predictive analytics systems.