Sentiment analysis: a review

Today, tourism and hospitality consumers are not isolated anymore when making purchase decisions. Social media represent support networks that allow these consumers to tap into a vast universe of peer opinions, critiques, feedback, recommendations or warnings about specific tourism and hospitality products or services (Benckendorff et al., 2014; Hvass & Munar, 2012; Miguéns et al., 2008; Milano et al., 2011; Munar & Jacobsen, 2014; Sigala et al., 2012; Thevenot, 2007; Xiang & Gretzel, 2010; Zeng & Gerritsen, 2014). This subjective and experience-based information can be expressed and published in diverse social media platforms such as forums, discussion groups, review platforms, personal blogs, public opinion blogs, microblogs and social networking sites but also visual platforms like You-Tube, Flickr, Instagram and Pinterest. Such social media content published by consumers is known as user-generated content in the current literature (Gretzel, 2015; Krumm et al., 2008). It has been considered by academics and practitioners as valuable information that can inform the emergence of new trends in markets, changes in the reputation of companies or destinations, consumer behaviors, processes of decision making and satisfaction/dissatisfaction with specific products/services (Liu, 2010; McGarrity, 2016)