Generalisation in Named Entity Recognition: A Quantitative Analysis
Table 1: Corpora genres and number of NEs of different classes
['[BOLD] Corpus', '[BOLD] Genre', '[BOLD] N', '[BOLD] PER', '[BOLD] LOC', '[BOLD] ORG']
Since the goal of this study is to compare NER performance on corpora from diverse domains and genres, seven benchmark NER corpora are included, spanning newswire, broadcast conversation, Web content, and social media (see These datasets were chosen such that they have been annotated with the same or very similar entity classes, in particular, names of people, locations, and organisations. Thus corpora including only domain-specific entities (e.g. biomedical corpora) were excluded. The choice of corpora was also motivated by their chronological age; we wanted to ensure a good temporal spread, in order to study possible effects of entity drift over time.