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world:enigmahanoi

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world:enigmahanoi [2020/03/19 17:50]
127.0.0.1 modification externe
world:enigmahanoi [2022/04/28 14:27] (current)
rdouc ↷ Page moved from public:enigmahanoi to world:enigmahanoi
Line 3: Line 3:
 ====== A first illustrative example ====== ====== A first illustrative example ======
  
-Two men are sitting in a bar. 
  
-> I am bored, man… +<​note ​tip>Two different real numbers are in a basket but we don't have access to their values. Pick at random one of them in the basket with equal probabilities and see its value. The question is to find a decision process which allows you to indicate, with a probability strictly larger than $1/2$, which one is the largest . </​note>​
->> Then, write two different real numbers on two papers and close them. +
-> Done. +
->> I will disclose only one of these papers. And I will tell you with probability strictly larger than 1/2, which paper contains the largest real number. +
-> You are kidding! How can you do that? +
- +
-<​note ​warning>Two different real numbers are in a basket but we don't have access to their values. Pick at random one of them in the basket with equal probabilities and see its value. The question is to find a decision process which allows you to indicate, with a probability strictly larger than $1/2$, which one is the largest . </​note>​+
  
 <hidden Answer> $ \newcommand{\rset}{\mathbb R} \newcommand{\PP}{\mathbb P}$ Denote by $X$ the chosen real number that you have in your hand. Let $\alpha: \rset \to (0,1)$ be a (strictly) increasing measurable function. With a probability $\alpha(X)$,​ say that the largest real number is the one in your hand and otherwise say that this is the one in the basket. <hidden Answer> $ \newcommand{\rset}{\mathbb R} \newcommand{\PP}{\mathbb P}$ Denote by $X$ the chosen real number that you have in your hand. Let $\alpha: \rset \to (0,1)$ be a (strictly) increasing measurable function. With a probability $\alpha(X)$,​ say that the largest real number is the one in your hand and otherwise say that this is the one in the basket.
world/enigmahanoi.1584636613.txt.gz · Last modified: 2022/03/16 01:33 (external edit)