| [ QuizWit ] in KIDS 글 쓴 이(By): cycho (멋진척™) 날 짜 (Date): 2001년 8월 27일 월요일 오후 11시 09분 17초 제 목(Title): Elementary Probability Abe, Bob and Cal are in prison. Two of them are scheduled to be put to death, but they do not know which of them has been selected. "Now," says Abe to the warden, "Since I know that either Bob or Cal or both are going to be executed, you will give me no information by telling me the name of one of them who will be execueted (if both Bob and Cal are, just tell me one at random)." The warden agrees and says, "Bob." Abe then concludes: "Since I now know that either Cal or myself will be executed, my probability of getting executed is 1/2." Cal, who overhears the above conversation between Abe and the warden, thinks for a minute, then says, "Great! My probability of getting executed is now only 1/3." There is an obvious mismatch between the statements of Abe and Cal, since one of the two will certainly be executed. Resolve this conflicting result. |