Rule strength measures (the transaction data set) if sup gor sup in T Support: The rule holds with support transactions containⅩ∪Y ◆Sp=Pr(x∪Y Confidence. The rule holds in t with confidence conf if conf of tranactions that contain x also contain y conf=Pr(r X) a An association rule is a pattern that states When x occurs. y occurs with certain probability9 Rule strength measures ◼ Support: The rule holds with support sup in T (the transaction data set) if sup % of transactions contain X  Y. ◆ sup = Pr(X  Y). ◼ Confidence: The rule holds in T with confidence conf if conf % of tranactions that contain X also contain Y. ◆ conf = Pr(Y | X) ◼ An association rule is a pattern that states when X occurs, Y occurs with certain probability