Análise de sentimentos

Abstract

Opinion mining and sentiment analysis is a fast growing topic with various world applications from polls, academic issues to advertisement placement. With the growing availability of online resources on Web and popularity of fast and rich resources of opinion sharing such as online review sites and personal blogs, opinion mining has become an interesting area of research. Opinion mining is a process, used for automatic extraction of knowledge from the opinion of others about some particular topic or problem. Further, opinions are subjective expressions that describe people's viewpoints, perspectives or feelings about entities, events and theirs properties. Detecting subjective expressions is the task of identifying whether a given text is subjective (i.e. an opinion) or objective (i.e. a reports fact). This task is considered as the first problem and it is very important for opinion mining and sentiment analysis. This research presents the current state of the art in opinion mining. We discover that research has been concentrated towards finding out the sentiment on an item and classifying it as thumbs up or down. Opinion mining has many application domains including science & technology, entertainment, education, politics, marketing, accounting, law, research and development. Since this field is very new and much work is currently being done in this area, we take the opportunity to categorize a significant part of the existing work in a way that can help researchers to study this field in further detail.