SYNONYMS NONE DEFINITION Information Extraction (IE) is a task of extracting pre-specified types of facts from written texts or speech transcripts, and converting them into structured representations (e.g., databases). IE terminologies are explained via an example as follows. Media tycoon Barry Diller on Wednesday quit as chief of Vivendi Universal Entertainment, the entertainment unit of French giant Vivendi Universal whose future appears up for grabs.-" End-Position " event. The above sentence includes a " Personnel_End-Position " event mention, with the trigger word which most clearly expresses the event occurrence, the position, the person who quit the position, the organization, and the time during which the event happened: Trigger Quit Person Barry Diller Media tycoon Organization Vivendi Universal Entertainment the entertainment unit of French giant Vivendi Universal Position Chief Time-within Wednesday Table 1. Event Extraction Example HISTORICAL BACKGROUND The earliest IE system was directed by Naomi Sager of the Linguistic String Project group [1] in the medical domain. However, the specific task of information extraction was formally evaluated through the There were four specific evaluations: Named entity, coreference and template element reflected in the evaluation tasks introduced for MUC-6, and template relation introduced in MUC-7.
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