Evaluation Exercises on Semantic Evaluation - ACL SigLex event
#11 Event Detection in Chinese News Sentences
Description The goal of the task is to detect and analyze some basic event contents in real world Chinese news texts. It consists of finding key verbs or verb phrases to describe these events in the Chinese sentences after word segmentation and part-of-speech tagging, selecting suitable situation description formula for them, and anchoring different situation arguments with suitable syntactic chunks in the sentence. Three main sub-tasks are as follows:
Target verb WSD: to recognize whether there are some key verbs or verb phrases to describe two focused event contents in the sentence, and select suitable situation description formula for these recognized key verbs (or verb phrases), from a situation network lexicon.
The input of the sub-task is a Chinese sentence annotated with correct word-segmentation and POS tags. Its output is the sense selection or disambiguation tags of the target verbs in the sentence.
Sentence SRL: to anchor different situation arguments with suitable syntactic chunks in the sentence, and annotate suitable syntactic constituent and functional tags for these arguments.
Its input is a Chinese sentence annotated with correct word-segmentation, POS tags and the sense tags of the target verbs in the sentence. Its output is the syntactic chunk recognition and situation argument anchoring results.
Event detection: to detect and analyze the special event content through the interaction of target verb WSD and sentence SRL.
Its input is a Chinese sentence annotated with correct word-segmentation and POS tags. Its output is a complete event description detected in the sentence (if it has a focused target verb).
The following is a detailed example to explain the above procedure:
For such a Chinese sentence after word-segmentation and POS tagging:
今天/n(Today) 我/r(I) 在/p(at) 书店/n(bookstore) 买/v(buy) 了/u(-ed) 三/m(three) 本/q 新/a(new) 书/n(book) 。/w (Today, I bought three new books at the bookstore.)
After the first processing stage: target verb WSD, we find there is a possession-transferring verb ‘买/v(buy)’ in the sentence and select the following situation description formula for it:
买/v(buy): DO(x, P(x,y)) CAUSE have(x,y) AND NOT have(z,y) [P=buy]
Then, we anchor four situation arguments with suitable syntactic chunks in the sentence and obtain the following sentence SRL result: