| is.generator {arules} | R Documentation |
Find Generator Itemsets
Description
Provides the generic function and the method 'is.generator() for finding generator itemsets. Generators are part of concise representations for frequent itemsets. A generator in a set of itemsets is an itemset that has no subset with the same support (Liu et al, 2008). Note that the empty set is by definition a generator, but it is typically not stored in the itemsets in arules.
Usage
is.generator(x)
## S4 method for signature 'itemsets'
is.generator(x)
Arguments
x |
a set of itemsets. |
Value
a logical vector with the same length as x indicating for
each element in x if it is a generator itemset.
Author(s)
Michael Hahsler
References
Yves Bastide, Niolas Pasquier, Rafik Taouil, Gerd Stumme, Lotfi Lakhal (2000). Mining Minimal Non-redundant Association Rules Using Frequent Closed Itemsets. In International Conference on Computational Logic, Lecture Notes in Computer Science (LNCS 1861). pages 972–986. doi:10.1007/3-540-44957-4_65
Guimei Liu, Jinyan Li, Limsoon Wong (2008). A new concise representation of frequent itemsets using generators and a positive border. Knowledge and Information Systems 17(1):35-56. doi:10.1007/s10115-007-0111-5
See Also
Other postprocessing:
is.closed(),
is.maximal(),
is.redundant(),
is.significant(),
is.superset()
Other associations functions:
abbreviate(),
associations-class,
c(),
duplicated(),
extract,
inspect(),
is.closed(),
is.maximal(),
is.redundant(),
is.significant(),
is.superset(),
itemsets-class,
match(),
rules-class,
sample(),
sets,
size(),
sort(),
unique()
Examples
# Example from Liu et al (2008)
trans_list <- list(
t1 = c("a","b","c"),
t2 = c("a","b", "c", "d"),
t3 = c("a","d"),
t4 = c("a","c")
)
trans <- transactions(trans_list)
its <- apriori(trans, support = 1/4, target = "frequent itemsets")
is.generator(its)