arules (version 1.7-6)

is.significant: Find Significant Rules

Description

Provides the generic functions is.significant() and the method to find significant rules.

Usage

is.significant(
  x,
  transactions,
  method = "fisher",
  alpha = 0.01,
  adjust = "bonferroni"
)
# S4 method for rules
is.significant(
  x,
  transactions,
  method = "fisher",
  alpha = 0.01,
  adjust = "bonferroni"
)

Value

returns a logical vector indicating which rules are significant.

Arguments

x

a set of rules.

transactions

set of transactions used to mine the rules.

method

test to use. Options are "fisher", "chisq". Note that the contingency table is likely to have cells with low expected values and that thus Fisher's Exact Test might be more appropriate than the chi-squared test.

alpha

required significance level.

adjust

method to adjust for multiple comparisons. Options are "none", "bonferroni", "holm", "fdr", etc. (see stats::p.adjust())

Author

Michael Hahsler

Details

The implementation for association rules uses Fisher's exact test with correction for multiple comparisons to test the null hypothesis that the LHS and the RHS of the rule are independent. Significant rules have a p-value less then the specified significance level alpha (the null hypothesis of independence is rejected). See Hahsler and Hornik (2007) for details.

References

Hahsler, Michael and Kurt Hornik (2007). New probabilistic interest measures for association rules. Intelligent Data Analysis, 11(5):437--455. tools:::Rd_expr_doi("10.3233/IDA-2007-11502")

See Also

stats::p.adjust()

Other interest measures: confint(), coverage(), interestMeasure(), is.redundant(), support()

Other postprocessing: is.closed(), is.generator(), is.maximal(), is.redundant(), is.superset()

Other associations functions: abbreviate(), associations-class, c(), duplicated(), extract, inspect(), is.closed(), is.generator(), is.maximal(), is.redundant(), is.superset(), itemsets-class, match(), rules-class, sample(), sets, size(), sort(), unique()

Examples

data("Income")
rules <- apriori(Income, parameter = list(support = 0.5))
is.significant(rules, Income)

inspect(rules[is.significant(rules, Income)])