The good, the bad and the implicit: a comprehensive approach to annotating explicit and implicit sentiment

• Published in: Language Resources and Evaluation Vol. 49; no. 3; pp. 685 - 720
• Main Authors: Van de Kauter, Marjan, Desmet, Bart, Hoste, Véronique
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01.09.2015; Springer Netherlands; Springer Nature B.V
• Subjects: Annotations; Classification; Computational Linguistics; Computer Science; Corpus linguistics; Data mining; Dutch language; English language; Information processing; Language and Literature; Linguistics; Orientation; Original Paper; Polarity; Sentences; Social Sciences; Subjectivity; Texts; United States > US; Sweden; Corpus annotation; Sentiment analysis; Polarity; Natural language processing
• ISSN: 1574-020X; 1572-8412; 1574-0218
• DOI: 10.1007/s10579-015-9297-4

We present a fine-grained scheme for the annotation of polar sentiment in text, that accounts for explicit sentiment (so-called private states), as well as implicit expressions of sentiment (polar facts). Polar expressions are annotated below sentence level and classified according to their subjectivity status. Additionally, they are linked to one or more targets with a specific polar orientation and intensity. Other components of the annotation scheme include source attribution and the identification and classification of expressions that modify polarity. In previous research, little attention has been given to implicit sentiment, which represents a substantial amount of the polar expressions encountered in our data. An English and Dutch corpus of financial newswire text, consisting of over 45,000 words each, was annotated using our scheme. A subset of this corpus was used to conduct an interannotator agreement study, which demonstrated that the proposed scheme can be used to reliably annotate explicit and implicit sentiment in real-world textual data, making the created corpora a useful resource for sentiment analysis.