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public:t-622-arti-14-1:lab_5_-_bayesian_networks [2014/03/04 10:54] stephanpublic:t-622-arti-14-1:lab_5_-_bayesian_networks [2024/04/29 13:33] (current) – external edit 127.0.0.1
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   * http://www.cs.cmu.edu/~javabayes/ (a slightly older Java applet)   * http://www.cs.cmu.edu/~javabayes/ (a slightly older Java applet)
  
-Here is a short explanation on how to use the first toolThe application has two tabs "Create" and "Solve". In "Create" you can create and modify a Bayesian network, in "Solve" you can compute arbitrary probabilities using the network.+==== Short explanation on how to use the first tool ==== 
 + 
 +The application has two tabs "Create" and "Solve". In "Create" you can create and modify a Bayesian network, in "Solve" you can compute arbitrary probabilities using the network.
 Suppose you have a network with nodes A and B, where B depends on A. Suppose you have a network with nodes A and B, where B depends on A.
 To create the network, you need to: To create the network, you need to:
   * create two nodes and give them the names A and B;   * create two nodes and give them the names A and B;
   * create an arc pointing from A to B;   * create an arc pointing from A to B;
-  * modify the probability tables of both nodes and set the probabilities <latex>$P(A)$, $P(B|A)$, $P(B|\neg A)$</latex>.+  * modify the probability tables of both nodes and set the probabilities <latex>$P(A)$</latex><latex>$P(B|A)$</latex><latex>$P(B|\neg A)$</latex>.
 Suppose you want to compute <latex>$P(\neg A|\neg B)$</latex>, that is, you want to know the probability for A being false after having observed B being false. Then you need to: Suppose you want to compute <latex>$P(\neg A|\neg B)$</latex>, that is, you want to know the probability for A being false after having observed B being false. Then you need to:
   * Go to the "Solve" tab;   * Go to the "Solve" tab;
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   * click on "Query" and then on node A (select Brief query mode if asked).   * click on "Query" and then on node A (select Brief query mode if asked).
   * You should now see the probabilities for <latex>$P(A)$</latex> and <latex>$P(\neg A)$</latex> under the condition that B = false.   * You should now see the probabilities for <latex>$P(A)$</latex> and <latex>$P(\neg A)$</latex> under the condition that B = false.
 +
 +==== Laws of Probabilities ====
  
 The following laws of probabilities might be helpful for developing formulas: The following laws of probabilities might be helpful for developing formulas:
/var/www/cadia.ru.is/wiki/data/attic/public/t-622-arti-14-1/lab_5_-_bayesian_networks.1393930477.txt.gz · Last modified: 2024/04/29 13:32 (external edit)

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