Paper: Recognizing Named Entities in Tweets

ACL ID P11-1037
Title Recognizing Named Entities in Tweets
Venue Annual Meeting of the Association of Computational Linguistics
Session Main Conference
Year 2011

The challenges of Named Entities Recogni- tion (NER) for tweets lie in the insufficient information in a tweet and the unavailabil- ity of training data. We propose to com- bine a K-Nearest Neighbors (KNN) classi- fier with a linear Conditional Random Fields (CRF) model under a semi-supervised learn- ing framework to tackle these challenges. The KNN based classifier conducts pre-labeling to collect global coarse evidence across tweets while the CRF model conducts sequential la- beling to capture fine-grained information en- coded in a tweet. The semi-supervised learn- ing plus the gazetteers alleviate the lack of training data. Extensive experiments show the advantages of our method over the baselines as well as the effectiveness of KNN and semi- supervised learning.