Apriori, A Depth First Implementation
نویسندگان
چکیده
We will discuss DF , the depth £rst implementation of APRIORI as devised in 1999 (see [8]). Given a database, this algorithm builds a trie in memory that contains all frequent itemsets, i.e., all sets that are contained in at least minsup transactions from the original database. Here minsup is a threshold value given in advance. In the trie, that is constructed by adding one item at a time, every path corresponds to a unique frequent itemset. We describe the algorithm in detail, derive theoretical formulas, and provide experiments.
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