BayesFusion Support Forum

Why should virtual evidence sum to 1? Have I understood correctly that when inserting virtual evidence you give the probability of observing a particular evidence E for all of the nodes states? P(E|node="state0"), P(E|node="state1"), P(E|node="state2"), and so on. If th...

When googlig this error the only thing I found was this answer in a stackoverflow question : A practical cause to "corrupted size vs. prev_size" is quite simple - memory chunk control structure fields in the adjacent following chunk are being overwritten due to out-of-bounds access by the ...

It seems that the error was caused by giving a (temporal) node virtual evidence with 0% probability for each outcome. The SetTemporalEvidence() function returned 0 indicating no error, and the error first occurred when trying to evaluate the network. I don't know if this is the case for non-temporal...

Hi! For some evidence configurations in my DBN I get a "corrupted size vs. prev_size" error when executing "UpdateBeliefs()" in c++. As it only occurs for some evidence configurations I thought it could be due to an impossible evidence configuration. To test this out I tried to i...

Hi Marke, thanks for cheking things out, no worries about the delay ;) Interesting that this uncovered a bug! If I'm not misunderstanding you, I think there is a misunderstanding on where I'm putting the evidence. I'm putting the evidence on the res and side nodes, not on the a and b nodes. In this ...

Hi Marek :) I might not completely understand how the marginalization works. I am for example not allowed to marginalize b1 or a1, but if I cut the connection from b1 to res1 (and redefine res1) then I can marginalize them. Furthermore, it does not seem like marginalization considers the inserted ev...

Hi, Marek, thanks for the great response again :) You are off-course correct. If I set evidence on side2 it will affect b2 which will affect b1 which will affect our believe on whether a1 or b1 caused res1. I was for some reason convinced that the Markov assumption would hold with a factored represe...

Hi! I'm struggling with the evaluation of the network not acting the way I would suspect. Se the following diagram: odd_evaluation.png This diagram mimics a dynamic net with 2 time-slices. The node res2 is of interest, this node has a definition that requires both a2 and b2 to be in state1 for it to...

Hi Marek, thank for the help! My DBN does contain a decision node but no utility. Does this affect things? I could just replace it with a chance node and set evidence on that node:) My variables have 7 states, i tried reducing them to 5 but that did not affect much. I also tried setting target nodes...

Hi Marek, thanks for the great reply! I completely understand the usefulness of your general approach enabling a wide range of models :) I don't really know what coopers algorithm is, it was taken from the error message I got from Python when the problem became too complicated: "Error when runn...

Hi! I am attempting to use DBNs for on-line decision making, where the system also needs to reason a bit backward in time as well as forwards. But I'm struggling with the computational time for some models and some scenarios suddenly becomes very high, or result in coopers algorithm not finding a so...