Frequent Item

A Frequent Item is an Item that occurs frequently in a Dataset.

See: Frequent Itemset, Frequent Item Finding Task, Data Stream, Set Cardinality.

References

(Cormode & Hadjieleftheriou) ⇒ Graham Cormode, and Marios Hadjieleftheriou. (2009). “Finding the Frequent Items in Streams of Data.” In: Communications of the ACM, 52(10). doi:10.1145/1562764.1562789
- The frequent items problem is to process a stream of items and find all those which occur more than a given fraction of the time. It is one of the most heavily studied problems in mining data streams, dating back to the 1980s. Many other applications rely directly or indirectly on finding the frequent items, and implementations are in use in large-scale industrial systems. In this paper, we describe the most important algorithms for this problem in a common framework. We place the different solutions in their historical context, and describe the connections between them, with the aim of clarifying some of the confusion that has surrounded their properties.