Appraisal of Opinion Expressions in Discourse Nicholas Asher, Farah Benamara and Yvette Yannick Mathieu IRIT-CNRS / LLF-CNRS Introduction Opinions are the common stock of conversation; and yet, like many facets of ev- ery day life, they are diicult to analyze precisely. Roughly, research in sentiment analysis comes in two lavors: a psychological one and a computational one. Psy- chologists propose cognitive theories of emotions and afect of various sorts. We distinguish three main approaches: the discrete approach where emotions are a small set of basic, innate and universal concepts (P. Ekman 1970) (C. Izard 1971), the dimensional approach which proposes dimensions underlying emotional con- cepts (Osgood et al. 1957) (J. Russell 1983) and inally, the appraisal approach where emotions are deined as the evaluation of the interaction between someone’s goals, beliefs, etc., and his environment (A. Ortony et al. 1988) (J. Martin and P. White 2005). Computational approaches to sentiment analysis eschew a general theory of emotions and focus on extracting the afective content of a text from the detection of expressions of sentiment. hese expressions are assigned a positive or a nega- tive scalar value, representing a positive, negative or neutral sentiment towards some topic. Using information retrieval, text mining and computational linguistic techniques (P. Turney 2002) (H. Yu and V. Hatzivassiloglou 2003) together with a set of dedicated linguistic resources, such as SentiWordNet (A. Esuli and F. Sebas- tiani 2006) one can calculate opinions exploiting the detected ”bag of sentiment words”. Related works include the detection of the opinion holder and the opinion topic (S. Kim and E. Hovy 2006) (S. Bethard et al. 2004). Recently, new methods for sentiment analysis aim to assign ine-grained afect labels based on various psychological theories–e.g., the WordNet Afect project (C. Strapparava and A. Valitutti 2004) based on Ortony’s salience imbalance theory (ibid.), the MPQA project (J. Wiebe et al. 2005) based on the notion of private state of (R. Quirk et al. 1985), and inally work by (C. Whitelaw et al. 2005) and (J. Read et al. 2007) based Lingvisticæ Investigationes 32:2 (2009), 279–292. doi 10.1075/li.32.2.10ash issn 0378–4169 / e-issn 1569–9927 © John Benjamins Publishing Company