Research on Typical Algorithms in Negative Sequential Pattern Mining

Abstract

Negative sequential pattern (NSP), which contains both non-occurring and occurring items, can discover much more interest roles than positive sequential pattern (PSP) in many applications. NSP mining, however, has been just caught attention and very limited methods are available to mine NSP. Furthermore, there is not a unified definition about negative containment, i.e., how a data sequence contains a negative sequence. The researchers who begin to study nega- tive sequential pattern are often confused by these different definitions and are eager to know the differences of the exist- ing methods. So in this paper, we select four typical existing methods, PNSP, Neg-GSP, e-NSP and NSPM, implement their algorithms by JAVA, and compare their definition, method, runtime and the number of NSPs. Examples and experi- ments on four dataset clearly show their differences.