Patent ID: 8463789

Claim:
A machine readable medium storing a program which when executed by at least one processing unit of a research system identifies an event for a category, the program comprising sets of instructions for: for each of a plurality of different pre-identified categories for which the research system stores retrievable data, classifying a first set of documents from a current time period and a second set of documents from a background time period as relevant to the category, wherein the current time period and the background time period are separated by a buffer time period in order to isolate the current time period from the background time period; for each of the plurality of categories, calculating a score for the category for the current time period that quantifies a relative difference in a size of the first set of documents from the current time period and a size of the second set of documents from the background time period; when the calculated score for a particular category is above a threshold, determining the occurrence of an event for the category in the current time period; and storing data in the research system indicating the occurrence of an event for each of the plurality of categories for which the calculated score is above the threshold.