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Classes of association rules short overview. Jan Rauch, Department of Knowledge and Information Engineering University of Economics, Prague. Classes of association rules – overview. Introduction, classes of rules and quantifiers Implicational quantifiers
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Classes of association rules short overview Jan Rauch, Department of Knowledge and Information Engineering University of Economics, Prague
Classes of association rules – overview • Introduction, classes of rules and quantifiers • Implicational quantifiers • Deduction rules for implicational quantifiers • Tables of critical frequencies for implicational quantifiers • -double implication 4ft quantifiers • - equivalence 4ft quantifiers • 4ft quantifiers with F-property
Classes of association rules – Introduction • Simple intuitive definition • Each class contains both simple association rules and comlex association rules corresponding to statistical hypothesis tests • Important both theoretical and practical properties • Examples: • imlicational association rules • double imlicationalassociation rules • -double imlicational association rules • equivalency association rules • - equivalency association rules • rules with F-property
Literature Hájek, P. - Havránek T.: Mechanising Hypothesis Formation – Mathematical Foundations for a General Theory. Berlin – Heidelberg - New York, Springer-Verlag, 1978, 396 pp, http://www.cs.cas.cz/~hajek/guhabook/ Rauch, J.: Logic of Association Rules. Applied Intelligence, 2005, No. 22, 9-28 Rauch, J.: Classes of Association Rules, An Overview. In: LIN, T.Y. Ying, X.(Ed.): Foundation of Semantic Oriented Data and Web Mining. Proceedings of an ICDM 2005 Workshop, IEEE Houston 2005. pp 68 – 74. http://www.cs.sjsu.edu/faculty/tylin/ICDM05/proceeding.pdf
Classes of 4ft-quantifiers Association rule belongs to the class of association rules if and only if the 4ft-quantifier belongs to the class of 4ft-quantifiers Examples: • association rule is implicational iff is implicational • association rule is -double implicational iff is -double implicational • association rule is - equivalency iff is - equivalency
M M’ a b a’ b’ c d c’ d’ * is implicational quantifier M’ is better from the point of view of implication: a’ a b’ b If *(a, b, c, d) = 1 and a’ a b’ b then *(a’, b’, c’, d’) = 1 Truth Preservation Condition for implicational quantifiers: TPC :a’ a b’ b * is implicational: If *(a, b, c, d) = 1 and TPC then *(a’, b’, c’, d’) = 1
Implication quantifiers – examples (1) Founded implication: p,B (a,b,c,d) = 1 iff a’ a b’ b: Founded 2b - implication: p,B (a,b,c,d) = 1 iff
Implication quantifiers – examples (2) Lower critical implication for0 < p 1, 0 0.5: !p; (a,b,c,d) = 1 iff The rule !p; corresponds to the statistical test (on the level )of the null hypothesis H0: P( | ) p againstthe alternative one H1: P( | ) > p. Here P( | ) is the conditional probability of thevalidity of under the condition . a’ a b’ b:
M M EF E E (EF) A a b A a’ b’ A c d A c’ d’ Deduction rules (1) Is the deduction rule correct? we see: a’ a b’ b and TPC thus if 0.9,50(a,b,c,d) = 1 then also 0.9, 50(a,b,c,d) = 1 Yes, the deduction rule is correct.
M M EF E E (EF) A a b A a’ b’ A c d A c’ d’ Deduction rules (2) Is the deduction rule correct? we see: a’ a b’ b and it is TPC and thus if !0.95,0.05(a,b,c,d) = 1 then also !0.95, 0.05(a,b,c,d) = 1 Yes, the deduction rule is correct.
Deduction rules (3) Additional correct deduction rules (prove it home): Question: * implication quantifier: iff ???
Deduction rules – two notions Associated propositional formula () associated to Boolean attribute : Rule p,B e.g. A B C p,B D E F A, B, C, B, D, E, Fare Boolean attributes ( ): Boolean attributes propositional variables () = A B C () = D E F A, B, C, D, E, F are propositional variables, we can decide if () is a tautology
Deduction rules – two notions Implicational quantifier is interesting: Iis a – dependent , b – dependent and(0,0,c,d) = 0 is a - dependent if exists a, a’, b, c, d : (a,b,c,d) (a’, b, c, d) 0.9, 50, !0.9, 0.05 are interesting implicationquantifiers
Correct Deduction Rules is thecorrect deduction ruleiff 1) or 2) are satisfied: 1) both (X) (Y) (X’) (Y’) and (X’) (Y’) (X) (Y) are tautologies 2) (X) (Y) is a tautology
Correct Deduction Rules Example: is correct because of A B EA (EB)and A ( E B) A BE are tautologies
Table of Critical Frequencies implication quantifier: if*(a, b, c, d) = 1and a’ a b’ b then*(a’, b’, c’, d’) = 1 *is c, d independent, thus *(a, b) instead of*(a, b, c, d) Table of maximal b for *:Tb*(a) = min {e|*(a, e) = 0} *(a, b)= 1 iff b < Tb* (a)
M’ M Y Y Y Y X X a a’ b’ b X X c c’ d’ d Class of -double implication 4ft quantifiers True Preservation Condition: a’ a b’ + c’ b + c example: X p Y a/(a + b + c) p TCF: Tb*(a) = min{b+c|*(a, b, c) = 0} *(a, b, c)= 1 iff b + c < Tb* (a) is correct iff ...
M’ M Y Y Y Y X X a a’ b’ b X X c c’ d’ d Class of - equivalence 4ft quantifiers True Preservation Condition: a’ + d’ a + d b’ + c’ b + c example:X p Y (a + d)/(a+b+c+d) p TCF: Tb*(F)=min {b+c | *(a,b,c,d)=0 a+d=F} *(a, b,c,d)= 1 iff b +c < Tb*(a + d) is correct iff ...
4ft quantifiers with F-property has the F-property if it satisfies If (a,b,c,d) = 1 and b c – 1 0 then(a,b+1,c-1,d)= 1 If (a,b,c,d) = 1 and c b – 1 0 then (a,b -1,c+1,d)= 1 If is symmetrical andhas the F-property then there is a function T(a,d,n) such that for a+b+c+d = n is (a,b,c,d) = 1 iff| b-c | T(a,d,n) Fisher’s quantifier and 2 quantifier have the F-property