Finding Frequent Elements in Non-bursty Streams

We present an algorithm for finding frequent elements in a stream where the arrivals are not bursty. Depending on the amount of burstiness in the stream our algorithm detects elements with frequency at least t with space between ˜O(F1/t2 ) and ˜O(F2/t2 ) where F1 and F2 are the first and the second frequency moments of the stream respectively. The latter space complexity is achieved when the stream is completely bursty; i.e., most elements arrive in contiguous groups, and the former is attained when the arrival order is random. Our space complexity is ˜O(αF1/t2 ) where α is a parameter that captures the burstiness of a

• Type: Conference
• Year: 2007
• Where: ESA
• Authors: Rina Panigrahy, Dilys Thomas
• Keywords: Algorithm Detects Elements, ESA 2007, Space Complexity, Stream