| 摘要 |
An event of interest is identified as trending if the number of occurrences of the event in a stream of documents is increasing or decreasing significantly from normal levels. Such a determination is made by comparing a number of occurrences in a recent time period to a long term average. An average number of occurrences over a given time period, and its variance, can be computed from historical information. The current number of occurrences also is computed for the most recent time period. Events, for which the current number is significantly different from the average level, by considering the variance, have statistically significant changes. |
