Data Mining Discussion 4 d

• How would you define an "uninteresting association rule"?

An uninteresting association rule is a misleading “strong” association rule. Just because an association rule meets the minimum support and confidence thresholds and have high values doesn’t necessarily mean the rule is interesting. In fact, it might be an outlier due to the data of each individual item.

• Why can the confidence of a rule A -> B be sometimes deceiving?

It doesn’t measure the lack of strength of the correlation and implication between A and B. It reflects an uninteresting association rule.

• What is a correlation rule?

A correlation rule is a strong association rule that has been modified with a correlation measure. It is a rule that not only is it measured by its support and confidence, but also by the correlation between the items. We can do correlation analysis by using the X^2 measure or Lift measure. The lift measure states that the the occurrence of itemset A is independent of the occurrence of itemset B if P(A U B) = P(A)P(B). Otherwise, itemsets A and B are dependent and correlated.

• Discuss any one of the pattern evaluation measures.

Max_Confidence measure: Given two itemsets (A and B), the max_confidence measure of A and B is max_conf(A, B) = max{P(A|B), P(B|A)}. The max_conf measure refers to the maximum confidence of the two association rules, A->B and B->A.