UCM-2: a Rule-Based Approach to Infer the Scope of Negation via Dependency Parsing

UCM-2 infers the words that are affected by negations by browsing dependency syntactic structures. It first makes use of an algorithm that detects negation cues, like no, not or nothing, and the words affected by them by traversing Minipar dependency structures. Second, the scope of these negation cues is computed by using a post-processing rulebased approach that takes into account the information provided by the first algorithm and simple linguistic clause boundaries. An initial version of the system was developed to handle the annotations of the Bioscope corpus. For the present version, we have changed, omitted or extended the rules and the lexicon of cues (allowing prefix and suffix negation cues, such as impossible or meaningless), to make it suitable for the present task.