| Introduction | As is common for many natural language processing problems, the state-of-the-art in noun phrase (NP) coreference resolution is typically quantified based on system performance on manually annotated text corpora. |
| Introduction | MUC-6 (1995), ACE NIST (2004)) and their use in many formal evaluations, as a field we can make surprisingly few conclusive statements about the state-of-the-art in NP coreference resolution . |
| Introduction | In particular, it remains difi‘icult to assess the effectiveness of diflerent coreference resolution approaches, even in relative terms. |