Naïve Bayes Classifier
n Calculate most probable function value
Vmap = argmax P(vj| a1,a2, … , an)
        = argmax P(a1,a2, … , an| vj) P(vj)
                               P(a1,a2, … , an)
        = argmax P(a1,a2, … , an| vj) P(vj)
Naïve assumption: P(a1,a2, … , an) = P(a1)P(a2) …
P(an)