See: Description
Interface  Description 

InterestingnessMeasure 
Interface for interestingness measures.

Class  Description 

AddedValue 
Added value (AV) interestingness measure:
\( \text{confidence}(X \rightarrow Y)  \text{support}(Y) = P(YX)P(Y) \).

CertaintyFactor 
Certainty factor (CF; Loevinger) interestingness measure.
\( \tfrac{\text{confidence}(X \rightarrow Y) 
\text{support}(Y)}{\text{support}(\neg Y)} \).

Confidence 
Confidence interestingness measure,
\( \tfrac{\text{support}(X \cup Y)}{\text{support}(X)}
= \tfrac{P(X \cap Y)}{P(X)}=P(YX) \).

Conviction 
Conviction interestingness measure:
\(\frac{P(X) P(\neg Y)}{P(X\cap\neg Y)}\).

Cosine 
Cosine interestingness measure,
\(\tfrac{\text{support}(A\cup B)}{\sqrt{\text{support}(A)\text{support}(B)}}
=\tfrac{P(A\cap B)}{\sqrt{P(A)P(B)}}\).

GiniIndex 
Giniindex based interestingness measure, using the weighted squared
conditional probabilities compared to the nonconditional priors.

Jaccard 
Jaccard interestingness measure:
\[\tfrac{\text{support}(A \cup B)}{\text{support}(A \cap B)}
=\tfrac{P(A \cap B)}{P(A)+P(B)P(A \cap B)}
=\tfrac{P(A \cap B)}{P(A \cup B)}\]
Reference:
P.

JMeasure 
JMeasure interestingness measure.

Klosgen 
Klösgen interestingness measure.

Leverage 
Leverage interestingness measure.

Lift 
Lift interestingness measure.

Much of the confusion with these measures arises from the antimonotonicity of itemsets, which are omnipresent in the literature.
In the itemset notation, the itemset \(X\) denotes the set of matching transactions \(\{TX\subseteq T\}\) that contain the itemset \(X\). If we enlarge \(Z=X\cup Y\), the resulting set shrinks: \(\{TZ\subseteq T\}=\{TX\subseteq T\}\cap\{TY\subseteq T\}\).
Because of this: \(\text{support}(X\cup Y) = P(X \cap Y)\) and \(\text{support}(X\cap Y) = P(X \cup Y)\). With "support" and "confidence", it is common to see the reversed semantics (the union on the constraints is the intersection on the matches, and conversely); with probabilities it is common to use "events" as in frequentist inference.
To make things worse, the "support" is sometimes in absolute (integer) counts, and sometimes used in a relative share.
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