Detecting New and Emerging Events from Textual Sources

Recognizing new and emerging events in a stream of news documents requires understanding the semantic structure of news reported in natural language. New event detection (NED) is the task of recognizing when a news document discusses a completely novel event. To be successful at this task, we argue a NED method must extract and represent the type of event and its participants as well as the temporal and spatial properties of the event. Our NED methods produce a 25% cost reduction over a bag-of-words baseline and a 13% cost reduction over an existing state-of-the-art approach. Additionally, we discuss our method for recognizing emerging events: the tracking and categorization of unexpected or novel events.