Title
Sentence-level event classification in unstructured texts
Abstract
The ability to correctly classify sentences that describe events is an important task for many natural language applications such as Question Answering (QA) and Text Summarisation. In this paper, we treat event detection as a sentence level text classification problem. Overall, we compare the performance of discriminative versus generative approaches to this task: namely, a Support Vector Machine (SVM) classifier versus a Language Modeling (LM) approach. We also investigate a rule-based method that uses handcrafted lists of `trigger' terms derived from WordNet. Two datasets are used in our experiments to test each approach on six different event types, i.e., Die, Attack, Injure, Meet, Transport and Charge-Indict. Our experimental results show that the trained SVM classifier significantly outperforms the simple rule-based system and language modeling approach on both datasets: ACE (F1 66% vs. 45% and 38%, respectively) and IBC (F1 92% vs. 88% and 74%, respectively). A detailed error analysis framework for the task is also provided which separates errors into different types: semantic, inference, continuous and trigger-less.
Year
DOI
Venue
2010
10.1007/s10791-009-9113-0
Inf. Retr.
Keywords
Field
DocType
Information extraction,Event detection,Language modeling,Machine learning
Question answering,Computer science,Support vector machine,Information extraction,Natural language,Artificial intelligence,Natural language processing,WordNet,Discriminative model,Sentence,Language model,Machine learning
Journal
Volume
Issue
ISSN
13
2
1386-4564
Citations 
PageRank 
References 
14
0.98
30
Authors
3
Name
Order
Citations
PageRank
M. Naughton1140.98
N. Stokes2140.98
J. Carthy3140.98