seqeconstraint: Setting time constraints and the counting method

Description

Function used to set time constraints and the counting method in methods (seqe...) for event sequences such as seqefsub for searching frequent subsequences or seqeapplysub for checking occurrences of subsequences.

Usage

seqeconstraint(max.gap = -1, window.size = -1, age.min = -1, age.max = -1,
  age.max.end = -1, count.method = 1, maxGap, windowSize, ageMin, ageMax,
ageMaxEnd, countMethod)

Arguments

max.gap

The maximum time gap between two events

window.size

The maximum time span accepted for subsequences

age.min

Minimal start time position allowed for subsequences. Ignored when equal to -1 (default).

age.max

Maximal start time position allowed for subsequences. Ignored when equal to -1 (default).

age.max.end

Maximal end time position allowed for subsequences. Ignored when equal to -1 (default).

count.method

By default, subsequences are counted only one time by sequence ('COBJ' method). Alternative counting methods are 'CDIST_O', 'CWIN', 'CMINWIN' or 'CDIST' respectively. See details.

maxGap

Deprecated. Use max.gap instead.

windowSize

Deprecated. Use window.size instead.

ageMin

Deprecated. Use age.min instead.

ageMax

Deprecated. Use age.max instead.

ageMaxEnd

Deprecated. Use age.max.end instead.

countMethod

Deprecated. Use count.method instead.

Value

A constraint object containing one item per constraint type.

Details

max.gap, window.size, age.min, age.max and age.max.end. If so, two events should not be separated by more than max.gap and the whole subsequence should not exceed a window.size time span. The other parameters specify the start and end age of the subsequence, it should start between age.min and age.max and finish before age.max.end. Parameters age.min, age.max and age.max.end are interpreted as the number of positions (time units) from the beginning of the sequence.

There are 5 options for the count.method argument. (1) By default, the count is the number of sequences that contain the subsequence ("COBJ" method). Alternatives are (2) "CDIST_O" (counts all distinct occurrences in each sequence including possibly overlapping occurrences, i.e., occurrences sharing a same event occurrence), (3) "CWIN" (number of slidden windows of length window.size that contain an occurrence of the subsequence), (4) "CMINWIN" (number of minimal windows of occurrence) and (5) "CDIST" (distinct occurrences without event occurrences overlap). See references.

References

Joshi, Mahesh V., George Karypis, and Vipin Kumar (2001) A Universal Formulation of Sequential Patterns Proceedings of the KDD'2001 Workshop on Temporal Data Mining, San Francisco.