Search found 23 matches
- Fri Jun 13, 2008 11:49 am
- Forum: SMILE
- Topic: calculating inferences
- Replies: 5
- Views: 6727
Re: calculating inferences
I had read out that, but tell me is it necessary to implement that algorithm for calculating inferences? I'm not quite sure what's your actual question. JT-based algorithm is one (arguably most commonly used) way to implement exact BN inference, but there are other exact algorithms. And if we imple...
- Thu Jun 12, 2008 1:23 pm
- Forum: SMILE
- Topic: calculating inferences
- Replies: 5
- Views: 6727
Re: calculating inferences
For notes on implementing algorithms based on junction tree, try "Inference in Belief Networks: A Procedural Guide" by Huang and Darwiche. Hi, I had read out that, but tell me is it necessary to implement that algorithm for calculating inferences? And if we implement that then do we have ...
- Thu Jun 12, 2008 11:30 am
- Forum: SMILE
- Topic: calculating inferences
- Replies: 5
- Views: 6727
calculating inferences
Hi All, Can anybody please tell me how to propagate through the network to calculate the posterior probabilities in bayesian network when no evidence is provided or a single or multiple evidences are provided by the user? :?: Is there any step by step methodology to be followed to get the inferences...
- Tue Apr 22, 2008 1:49 pm
- Forum: SMILE
- Topic: About learning
- Replies: 25
- Views: 25052
Hello Mark, As I've asked u earlier regarding the zero probabilities(i.e. wht if certain parents states combination is appearing 0 times) and how genie handled that situation, I think in that case laplace correction must have been applied, right? b'coz in that case only it gives those probability ca...
- Mon Apr 14, 2008 2:56 pm
- Forum: SMILE
- Topic: Regarding probability propagation
- Replies: 11
- Views: 11673
hi, when we set evidences for more than one variable then while claculating the inferences/ marginal probabilities for other variables how the probabilities associated with previous evidnce are propagated for calculating the probabilities with 2nd/new evidence for all other variables? can u please g...
- Mon Apr 14, 2008 12:57 pm
- Forum: SMILE
- Topic: About learning
- Replies: 25
- Views: 25052
- Thu Apr 10, 2008 2:52 pm
- Forum: SMILE
- Topic: Regarding probability propagation
- Replies: 11
- Views: 11673
Hi, when we set a particular value for a node in network, then while inferencing we need to calculate postrior probabilities for other nodes, using bayes formula, right? Now suppose i've node A with two values a1, a2 and P(a1) = 0.6 and P(a2) = 0.4 , now if i set the value for that node as a1, does ...
- Tue Apr 08, 2008 4:21 am
- Forum: SMILE
- Topic: About learning
- Replies: 25
- Views: 25052
Actually, Mark the same confusion again, before applying EM when the probabilities are assigned to states, there are some parent states combination which appears 0 times in data, but still there are probabilities assigned to those states. similarly some parentchild combination also appears 0 times i...
- Mon Apr 07, 2008 2:19 pm
- Forum: SMILE
- Topic: About learning
- Replies: 25
- Views: 25052
- Sat Mar 29, 2008 7:31 pm
- Forum: SMILE
- Topic: About learning
- Replies: 25
- Views: 25052
ok and when any particular combination of states of parent and child occurs '0' times then it gives conditional probability of child as '0' and in case if any particular combination of parents states appear '0' times then then the value of conditional probability of child will be 'infinity' and acco...
- Fri Mar 28, 2008 6:39 pm
- Forum: SMILE
- Topic: About learning
- Replies: 25
- Views: 25052
- Fri Mar 28, 2008 6:05 pm
- Forum: SMILE
- Topic: About learning
- Replies: 25
- Views: 25052
Hi, But can you please help me out to know these things? B'coz i'm trying to do it from many days but not getting my calculations correct. and actually somebody has told me to use parents CPT to calculate childs CPT and it has really confused me b'coz from programming perspective also it will be too...
- Fri Mar 28, 2008 10:08 am
- Forum: SMILE
- Topic: About learning
- Replies: 25
- Views: 25052
Hi, also while calculating CPT for node rejr in the same example of retention_discretized.txt, for many states of rejr, probability comes 'infinity', as the probability of occurence of many combinations of parents values are '0' and hence dividing probabiity of child, parent comb by these prob(havin...
- Fri Mar 28, 2008 6:50 am
- Forum: SMILE
- Topic: About learning
- Replies: 25
- Views: 25052
- Thu Mar 27, 2008 7:11 pm
- Forum: SMILE
- Topic: Regarding probability propagation
- Replies: 11
- Views: 11673