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ããç¨æ°å¦çè¯è¨æ¥è¡¨è¾¾ï¼å°±æ¯å·²ç¥P(apple) = N / (N + M), P(pear) = M / (N + M), P(yellow|apple) = 20%, P(yellow|pear) = 80%, æ±P(pear|yellow).
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ãã对äº1) æ们å¯ä»¥å¾å° P(yellow) * (N + M), P(yellow) = p(apple) * P(yellow|apple) + P(pear) * p(yellow|pear)
ãã对äº2) æ们å¯ä»¥å¾å° P(yellow|pear) * M
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¬å¼å¯ä»¥åæï¼P(A|B) = P(A,B) / P(B), å¯å¾ï¼P(A,B) = P(A|B) * P(B).è´å¶æ¯å
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