A new Frequency Estimation Sketch for Data Streams

In data stream applications, one of the critical issues is to estimate the frequency of each item in the specific multiset. The multiset means that each item in this set can appear multiple times. The data streams in many applications are high-speed streams which contain massive data, such as real-time IP traffic, graph streams, web clicks and crawls, sensor database, and natural language processing (NLP) [2][6], etc. In these applications, the stream information needs to be recorded by the servers in real time. However, since the data streams in these applications are high-speed, the accurate recording and estimation of item frequencies is always impractical. An alternative approach for addressing this problem is to estimate the item frequencies based on probabilistic data structures, and this approach has been widely used in the high-speed data streams estimation [7][9]. Sketches is one of the typical probabilistic data structures, which are initially designed for the estimation of item frequencies in data streams [10][15]. At present, the sketches have been used in many different scenarios, such as sparse approximation in compressed sensing [16], natural language processing [17, 18], data graph [19, 20], and more [21]. In this paper, we mainly focus on the sketches used for frequency estimation.