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Messages - uppglassmel

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I am going through some examples from F.V. Jensen's book from

Solutions -> Chapter 3-> Models and one called ex.3.10. It is a Dynamic Bayesian Belief Network on testing for infection in cow's milk.

I tried to open the file and it returned the error that the file cannot be loaded: expected 'class' keyword in line 1

Is there something I can do to open that file (attached here)?

Thank you

General Discussion / Re: Expressing Fault Tree Analysis in BBN
« on: June 07, 2018, 12:06:16  »
Hej Anders,

Thank you for the tips, I will try it out!

Appreciate your time


General Discussion / Re: Expressing Fault Tree Analysis in BBN
« on: June 02, 2018, 21:12:10  »
Hi Anders,

I would like to find out, if I have a node C4 with three states (Correct, Defective, Failure) can the NOISY-ADD still be used to implement a multi-state node as a Fault Tree encoded in a BBN.

As an AND gate:
How C4 should affect C1 is that when C4 = Defective or C4 =Failure, C1 should be simulated as

and P(C1=true|C2=true,C3=true, C4=Defective)=0.3*0.3*0.0099=0.000891

and P(C1=true|C2=true,C3=true, C4=Failure)=0.3*0.3*0.0001=0.000009

and that P(C1=False) whenever either one of or all of C4, C3, C2 takes on (False, Correct)

e.g. P(C1=False|C2=False,C3=False, C4=correct)=0.7*0.7*0.99=0.4851,

And also, as an OR gate, how should one encode it?

P(C1=False) when either C4,C3 and C2 takes on (Correct, False)
P(C1=True) when either C4,C3 and C2 takes on (Defective, Failure, True)

Thank you for your time

General Discussion / Re: Expressing Fault Tree Analysis in BBN
« on: April 10, 2018, 16:49:47  »
Hej Anders,

Thank you for showing me the 'noisy-add' gate, it worked for an OR-gate as well.

Attached it here in case someone else might be interested in it

Very appreciative of your time!


General Discussion / Expressing Fault Tree Analysis in BBN
« on: April 06, 2018, 17:01:10  »

I am interested in using BBN to modify probabilities that are being fed into a Fault Tree event node. Hence, I would like to also incorporate the Fault Tree Analysis as part of the BBN node.

I have seen some researchers (J.E. Vinnem et al "Risk Modelling of maintenance work on major process equipment on offshore petroleum installations") where they have configured Fault Tree gates in HUGIN by having inputs as "1" or "0" according to the states of the child node such they it resemble a AND-gate or OR-gate.

I have done the same, but my outcome node's results are only "1" or "0" because the values in the conditional probability tables(meant to describe the node as AND or OR gates) are propagated as the actual probabilities.

Do you have any advice what I can do ( my model is attached).

I mean to model C1 as a outcome node, with C2 (0.7 False, 0.3 True) and C3 (0.7 False, 0.3 True) as the input nodes. Based on C1 having the nature of an AND-gate, if I feed evidence that C2 and C3 is true, then I would like to see C1 being reflected as (0.3 X 0.3 = 0.09 that True will occur).

Thank you in advance, I hope I have been clear


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