A. The validation error rate is the only reliable measure for selecting models even if the validation set is too small.

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A. The validation error rate is the only reliable measure for selecting models even if the validation set is too small.
B. The conditional probability of variable Y given variable X, P(Y|X) is equal to the joint probability of X and Y, P(X, Y) divided by the probability of Y, P(Y).
C. Consider a transaction dataset that contains five items, {A,B,C,D,E}. Suppose the support of itemset {A, B} is the same as the support of itemset {A, B, C}, then the confidence of the rule {A, B} ⇒ {C} is 80%.