Difficulty: Easy
Correct Answer: Confidence.
Explanation:
Introduction / Context:
Association rule mining (Market Basket analysis) uses three core measures—support, confidence, and lift—to quantify relationships like “if C then D.” Understanding the difference between these measures is essential for evaluating cross-sell opportunities and designing promotions.
Given Data / Assumptions:
Concept / Approach:
Support measures how often items occur together: support(C ∧ D) = count(C and D) / total_transactions. Confidence measures the rule strength when the antecedent occurs: confidence(C → D) = support(C ∧ D) / support(C) = P(D | C). Lift normalizes confidence by the base rate of D: lift(C → D) = confidence(C → D) / support(D).
Step-by-Step Solution:
Verification / Alternative check:
Any text on association rules (Apriori, FP-Growth) defines confidence as a conditional probability given the antecedent, aligning with P(D | C).
Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:
Confidence.
Discussion & Comments