“…While most works approach it as a simple categorization problem, sentiment analysis is actually a suitcase research problem [17] that requires tackling many NLP tasks, including word polarity disambiguation [18], subjectivity detection [19], personality recognition [20], microtext normalization [21], concept extraction [22], time tagging [23], and aspect extraction [24]. Sentiment analysis has raised growing interest both within the scientific community, leading to many exciting open challenges, as well as in the business world, due to the remarkable benefits to be had from financial [25] and political [26] forecasting, e-health [27] and e-tourism [28], user profiling [29] and community detection [30], manufacturing and supply chain applications [31], human communication comprehension [32] and dialogue systems [33], etc.…”