11. ベイズ規則
0 P (A) 1
P (A, B) = P (A B) = P (A|B)P (B) = P (B|A)P (A)
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P (B) = P (A, B) + P (A, B)
ベイズ規則(Bayes’ rule)
P (B|A)P (A) P (B|A)
P (A|B) = = P (A)
P (B) X {A,A} P (B|X)P (X)
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P (A|B) : 事後確率
確率の変化
P (A) : 事前確率 P (A) P (A)
Odds: O(A) = P (A) = 1 P (A)
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