Feature-Rich Named Entity Recognition for Bulgarian Using Conditional Random Fields

Autor: Georgiev, Georgi, Nakov, Preslav, Ganchev, Kuzman, Osenova, Petya, Simov, Kiril Ivanov
Rok vydání: 2021
Předmět:
Zdroj: RANLP-2009
Druh dokumentu: Working Paper
Popis: The paper presents a feature-rich approach to the automatic recognition and categorization of named entities (persons, organizations, locations, and miscellaneous) in news text for Bulgarian. We combine well-established features used for other languages with language-specific lexical, syntactic and morphological information. In particular, we make use of the rich tagset annotation of the BulTreeBank (680 morpho-syntactic tags), from which we derive suitable task-specific tagsets (local and nonlocal). We further add domain-specific gazetteers and additional unlabeled data, achieving F1=89.4%, which is comparable to the state-of-the-art results for English.
Comment: named entity recognition, NER, conditional random fields, CRF, Bulgarian, BulTreeBank
Databáze: arXiv