In this paper, we describe HeidelTime, a system for the extraction and normalization of temporal expressions. HeidelTime is a rule-based system mainly using regular expression patterns for the extraction of temporal expressions and knowledge resources as well as linguistic clues for their normalization. In the TempEval-2 challenge, HeidelTime achieved the highest FScore (86%) for the extraction and the best results in assigning the correct value attribute, i.e., in understanding the semantics of the temporal expressions.
HeidelTime REF , an instance of the systems, outperformed the other systems the English temporal expression identification and normalization task of the TempEval 2 challenge.
HeidelTime: High Quality Rule-Based Extraction and Normalization of Temporal Expressions
Workshop on Semantic Evaluations (SemEval)
Computer Science