Comparisons of typical algorithms in negative sequential pattern mining

Negative sequential pattern (NSP), which contains both non-occurring and occurring items, can play more important 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. So in this paper, we select three typical existing methods, PNSP, Neg-GSP and e-NSP, and compare their definitions, runtime and the number of NSPs. Examples and experiments on same dataset clearly show their differences.