Effective Feature Selection Methods for User Sentiment Analysis using Machine Learning

Text classification is the method of allocating a particular piece of text to one or more of a number of predetermined categories or labels. This is done by training a machine learning model on a labeled dataset, where the texts and their corresponding labels are provided. The model then learns to predict the labels of new, unseen texts. Feature selection is a significant step in text classification as it helps to identify the most relevant features or words in the text that are useful for predicting the label. This can include things like specific keywords or phrases, or even the frequency or placement of certain words in the text. The performance of the model can be improved by focusing on the features that are most important to the information that is most likely to be useful for classification. Additionally, feature selection can also help to reduce the dimensionality of the dataset, making the model more efficient and easier to interpret. A method for extracting aspect terms from product reviews is presented in the research paper. This method makes use of the Gini index, information gain, and feature selection in conjunction with the Machine learning classifiers. In the proposed method, which is referred to as wRMR, the Gini index and information gain are utilized for feature selection. Following that, machine learning classifiers are utilized in order to extract aspect terms from product reviews. A set of customer testimonials is used to assess how well the projected method works, and the findings indicate that in terms of the extraction of aspect terms, the method that has been proposed is superior to the method that has been traditionally used. In addition, the recommended approach is contrasted with methods that are currently thought of as being state-of-the-art, and the comparison reveals that the proposed method achieves superior performance compared to the other methods. In general, the method that was presented provides a promising solution for the extraction of aspect terms, and it can also be utilized for other natural language processing tasks

An alternative framework for univariate filter based feature selection for text categorization

In this paper, we introduce an alternative framework for selecting a most relevant subset of the original set of features for the purpose of text categorization. Given a feature set and a local feature evaluation function (such as chi-square measure, mutual information etc.,) the proposed framework ranks the features in groups instead of ranking individual features. A group of features with rth rank is more powerful than the group of features with (r+1)th rank. Each group is made up of a subset of features which are supposed to be capable of discriminating every class from every other class. The added advantage of the proposed framework is that it automatically eliminates the redundant features while selecting features without requirement of study of features in combination. Further the proposed framework also helps in handling overlapping classes effectively through selection of low ranked yet powerful features. An extensive experimentation has been conducted on three benchmarking datasets using four different local feature evaluation functions with Support Vector Machine and Naïve Bayes classifiers to bring out the effectiveness of the proposed framework over the respective conventional counterparts