Assume we have 100 transactions and 20 items in our market basket. If the support for item an is 25%, the support for item b is 90%, and the support for itemset a, b is 20%. Let the support and confidence thresholds be 10% and 60%, respectively.

(a)

Calculate the confidence in the association rule a->b. According to the confidence measure, is the rule interesting?

(b)

Calculate the interest measure for the a, b association pattern. Describe the nature of the interest measure relationship between item a and item b.

(c)

What are your thoughts on the results of parts (a) and (b)?