Coding boolean statements

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fabrice.stephenson
Posts: 2
Joined: Wed Dec 13, 2023 10:26 am

Coding boolean statements

Post by fabrice.stephenson »

Hi there,

I have a question about implementing boolean statements.

I have a parent node with 3 states: high, moderate, low (standard chance node). I would like for a child node (2 states: yes / no) to either be 100% probability of yes or no based on a boolean statement.

For example, if "low" > = 0.7 in the parent node then I want the child node, "yes" = 100%.

Is there a way to implement this in GeNIe?

Many thanks for any help!
Fabrice
marek [BayesFusion]
Site Admin
Posts: 430
Joined: Tue Dec 11, 2007 4:24 pm

Re: Coding boolean statements

Post by marek [BayesFusion] »

Hi Fabrice,

What you want to do mixes values (high, moderate, and low) with uncertainty about them (probability of "low" > 0.7). Bayesian networks are models consisting of variables, each of which has its domain (these are values), and interactions among them, which can be best thought of as functions (mapping values of parents to the values of children with some uncertainty, expressed by the conditional probability distributions of the child, conditional on the parents). Defining the child node in terms of a function of the posterior marginal probability distribution over the parent would mix values with uncertainties over them. In general it would also be unsolvable, as the posteriors of the parents may depend on observed children (or descendants in general). You cannot do it.
I hope this helps,

Marek
fabrice.stephenson
Posts: 2
Joined: Wed Dec 13, 2023 10:26 am

Re: Coding boolean statements

Post by fabrice.stephenson »

Many thanks for the quick reply Marek - that clarifies things.
Best wishes,
Fabice
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