Topic Detection and Tracking (TDT) is a Body of Research and an Evaluation Paradigm that Addresses Event-Based Organization of Broadcast News. The TDT Evaluation Tasks of Tracking, Cluster Detection, and First Story Detection are Each Information Filtering Technology in the Sense That They Require That ‘yes or no’ Decisions be Made on a Stream of News Stories Before Additional Stories Have Arrived.
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Topic Detection and Tracking (TDT) google