Uncertainty identification is an important semantic processing task, which is critical to the quality of information in terms of factuality in many NLP techniques and applications, such as question answering, information extraction, and so on. Especially in social media, the factuality becomes a primary concern, because the social media texts are usually written wildly. The lack of open uncertainty corpus for Chinese social media contexts bring limitations for many social media oriented applications. In this work, we present the first open uncertainty corpus of microblogs in Chinese, namely, the UIR Uncertainty Corpus (UUC). At current stage, we annotated 40,168 Chinese microblogs from Sina Microblog. The schema of CoNLL 2010 have been adapted, where the corpus contains annotations at each microblog level for uncertainty and 6 sub-classes with 11,071 microblogs under uncertainty. To adapt to the characteristics of social media, we identify the uncertainty based on the contextual uncertain semantics rather than the traditional cue-phrases, and the sub-class could provide more information for research on handing uncertainty in social media texts. The Kappa value indicated that our annotation results were substantially reliable.

Keywords: Chinese Microblog, Uncertainty Annotation, UIR Uncertainty Corpus