Sundarapandian et al. (Eds) : ACITY, AIAA, CNSA, DPPR, NeCoM, WeST, DMS, P2PTM, VLSI - 2013 pp. 85–94, 2013. © CS & IT-CSCP 2013 DOI : 10.5121/csit.2013.3410          Pravesh Kumar Singh 1 , Mohd Shahid Husain 2 1 M.Tech, Department of Computer Science and Engineering, Integral University, Lucknow, India erpraveshkumar@gmail.com 2 Assistant Professor, Department of Computer Science and Engineering, Integral University, Lucknow, India siddiquisahil@gmail.com ABSTRACT Although opinion mining is in a nascent stage of development but still the ground is set for dense growth of researches in the field. One of the important activities of opinion mining is to extract opinions of people based on characteristics of the object under study. Feature extraction in opinion mining can be done by various ways like that of clustering, support vector machines etc. This paper is an attempt to appraise the various techniques of feature extraction. The first part discusses various techniques and second part makes a detailed appraisal of the major techniques used for feature extraction. KEYWORDS Opinion Mining, Feature Extraction, Clustering, Support Vector Machines. 1. INTRODUCTION People are generally more interested in other’s opinion and when it comes to company product then it becomes even more important. So, the information gathering behaviour makes us to collect and understand other’s views. Increasing networking capabilities provide a way for surprisingly large multitude of resources that contains options like blogs, reviews etc. As a result, now businesses are trying to analyse these floating opinions for competitive advan- tages. Now with the burst of activities in the area of sen- timent analysis they deal with opinions in the first class object as there is increasing interest in the systems of opinion mining. A fundamental step in opinion-mining and sentiment- analysis applications is feature extraction. The combined opinion mining procedure is illustrated in figure 1. Several methods are used for feature extraction among which, fol- lowing are the important ones: 1) Naïve –Bayes Classifier (NB) 2) Support Vector Machine (SVM) Opinions Feature Extraction Sentence Opinion Sentence Analysis Overall Review Score Calculation Results and Reviews Figure 1: Opinion Mining Process Sentence Extraction