Which of the following correctly defines lift?

Subject: Machine Learning

Topic: K-Means & Clustering in Unsupervised Learning

Options:

1. Option A: Lift(A -> B) = P(A∪B) / (P(A) * P(B))
2. Option B: Lift(A -> B) = P(A∪B) / P(A)
3. Option C: Lift(A -> B) = P(A∪B) / P(B)
4. Option D: Lift(A -> B) = P(A) * P(B) / P(A∪B)

Correct Answer:

Option A: Lift(A -> B) = P(A∪B) / (P(A) * P(B))

Explanation:

Lift measures the ratio of the observed support to the expected support if A and B were independent. Lift = P(A∪B) / (P(A)P(B)).