Effective Use of Evaluation Measures for the Validation of Best Classifier in Urdu Sentiment Analysis

Sentiment analysis (SA) can help in decision making, drawing conclusion, or recommending appropriate solution for different business, political, or other problems. At the same time reliable ways are also required to verify the results that are achieved after SA. In the frame of biologically inspired approaches for machine learning, getting reliable result is challenging but important. Properly verified and validated results are always appreciated and preferred by the research community. The strategy of achieving reliable result is adopted in this research by using three standard evaluation measures. First, SA of Urdu is performed. After collection and annotation of data, five classifiers, i.e., PART, Naives Bayes mutinomial Text, Lib SVM (support vector machine), decision tree (J48), and k nearest neighbor (KNN, IBK) are employed using Weka. After using 10-fold cross-validation, three top most classifiers, i.e., Lib SVM, J48, and IBK are selected on the basis of high accuracy, precision, recall, and F-measure. Further, IBK resulted as the best classifier among the three. For verification of this result, labels of the sentences (positive, negative, or neutral) are predicted by using training and test data, followed by the application of the three standard evaluation measures, i.e., McNemar's test, kappa statistic, and root mean squared error. IBK performs much better than the other two classifiers. To make this result more reliable, a number of steps are taken including the use of three evaluation measures for getting a confirmed and validated result which is the main contribution of this research. It is concluded with confidence that IBK is the best classifier in this case.