项约束频繁项集挖掘的新方法

项约束频繁项集挖掘是项约束关联规则挖掘的关键步骤。对项约束频繁项集挖掘的内涵进行讨论，认为一个项集X本身满足项约束条件B是不够的，数据库中支持X的全部事务均满足B才能称“项集X满足条件B”。据此，将Direct算法改进为Direct*，在Direct*中负项被作为一个独立的项来看待。项约束是简洁性约束，但目前已有的算法没有充分利用其简洁性，提出利用项约束简洁性的MSEB算法。实验表明：对稠密数据库，MSEB的效率较高，并且Direct*和MSEB两个算法均是正确的。

New method for mining frequent itemsets with item constraints

Mining frequent itemsets with item constraints is a key step for mining association rules with item constraints.The meaning of mining frequent itemsets with item constraints is discussed first,the paper affirms that an itemset X satisfy an item constraints B by itself is not enough.It can be said X satisfy B only if all transactions that support the X satisfy the B.Based on this point,the algorithm Direct is modified to be Direct*.A negative item is looked as an independent item in Direct*.Item con- straint...