Sequential Pattern Mining: Example II (Cont.)


The large sequences together with their support at the end of the second, third, and fourth passes are in the following three figures. No candidate is generated for the fourth pass. So the algorithm stops at L4.

Step 5. Maximal Phase finds the three maximal large sequences among the set of large sequences, the sequential patterns:

    1, 2, 3, 4,
    1, 3, 5, and
    4, 5

Other sequences may be large/frequent, but not maximal.

For example, the sequence 1, 2, 4 is large because its support 2 40%, but not maximal because it is contained in the sequence 1, 2, 3, 4