support-methods: Support Counting for Sequences

In arulesSequences: Mining Frequent Sequences

Support Counting for Sequences

Description

Compute the relative or absolute support of an arbitrary collection of sequences among a set of transactions with additional sequence and temporal information.

Usage

## S4 method for signature 'sequences'
support(x, transactions, type= c("relative", "absolute"),
           control = NULL)

## S4 method for signature 'sequences'
supportingTransactions(x, transactions, ...)

Arguments

x	an object.
transactions	an object of class transactions or sequences.
type	a character value specifying the scale of support (relative or absolute).
control	a named list with logical component verbose specifying if progress and runtime information should be displayed and list component parameter (see details).
...	currently not used.

Details

Provides support counting using either method ptree (default), or idlists (for details see the reference in cspade) and timing constraints.

parameter can be an object of class SPparameter or a named list with corresponding components. Note that constraints which do not relate to the timing information of transactions are ignored.

If sequences are used for transactions missing event times are replaced with the order indexes of events.

The supporting sequences are all sequences (of transactions) of which the sequence representing the association is a subset of.

Note that supportingTransactions does not support timing constraints.

Value

For support a numeric vector the elements of which correspond with the elements of x.

For supportingTransactions an object of class tidLists containing one sequence ID list per association in x.

Author(s)

Christian Buchta

See Also

Class sequences, method ruleInduction, function cspade, read_baskets.

Examples

## continue example
example(cspade)

## recompute support
s <- support(s2, zaki, control = list(verbose = TRUE, 
                     parameter = list(maxwin = 5)))
data.frame(as(s2, "data.frame"), support = s)

## use default method
k <- support(s2, zaki, control = list(verbose = TRUE))
table(size(s2), sign(k - s))

## the same
s <- supportingTransactions(s2, zaki)
itemFrequency(s)

arulesSequences documentation built on Sept. 11, 2024, 9:35 p.m.