快速频繁序列模式挖掘算法

为解决从数据库中挖掘长模式可能遇到较高的计算复杂度问题, 提出一种新的算法FFSPAN. 传统上， 要判断一个序列是否频繁, 需要在原数据库中判断整个序列是否频繁； 而算法FFSPAN是通过在序列数据库中寻找一个频繁项或一个频繁项集来代替寻找一个完整的频繁序列， 而且FFSPAN算法每次扫描的数据库都是迅速减小的, 这使得算法在挖掘的序列模式越长时越有效. 在标准测试数据集上的实验结果表明， FFSPAN算法非常有效.

Fast Frequent Sequential Pattern Mining Algorithm

A novel algorithm FFSPAN(fast frequent sequential pattern mining algorithm) is proposed to solve the problem that the computational complexity may become very high when mining long patterns in a(sequence) database.Traditionally,to judge whether a sub-sequence is frequent in a database,one need to compare the whole sub-sequence with every sequence in the original database,however the algorithm FFSPAN succeeds in solving the problem that in a sequence database,instead of searching a whole frequent sequence,we only need to search a frequent item or a frequent itemset.Moreover,the databases scanned via FFSPAN keep shrinking,which makes the algorithm more efficient when the sequential patterns are longer.Experiments on standard test data show that FFSPAN is very effective.