Finding Property

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HAPI
   |
   HAPI.Node
      |
      Finding(lStateIndex As Long) [[As Single]]

Syntax

Property Finding(lStateIndex As Long) [[As Single]]

Access

read/write

Parameter description

NameTypeDescription
lStateIndexLong The index of the state.

Description

The Finding property holds entered evidence for one state of a discrete chance node or a decision node in a compiled domain (see Compile). If a node has 3 states, evidence is entered by setting the value of Finding(0), Finding(1), and Finding(2) (thus, what you specify is an evidence vector. In most cases, you would (should) want to enter only '0's and '1's in the findings vector, but you can also enter values between 0 and 1. This is called likelihood evidence and you should be sure what you are doing before you use it (if you don't see any problem, DON'T enter finding values different from 0 and 1).

The SelectState method sets the Finding value of one state to 1 and all other to 0.

Example: Imagine you have a Bbn helping you playing some game of cards. You have a node named "spades" with states 0,1,...,13 representing the number of spades held by one of your opponents. During play, by mistake your opponent drops a card on the table and you observe that this card is the ace of spades. Now, you know that he/she has at least 1 spade. The way this is entered as evidence is by assigning 1 to the Finding property for all states except state 0 which is assigned 0:

 Set spades = CardGameDomain.GetNodeByName("spades")
spades.Finding(0) = 0
spades.Finding(1) = 1
spades.Finding(2) = 1
spades.Finding(3) = 1
spades.Finding(4) = 1
spades.Finding(5) = 1
spades.Finding(6) = 1
spades.Finding(7) = 1
spades.Finding(8) = 1
spades.Finding(9) = 1
spades.Finding(10) = 1
spades.Finding(11) = 1
spades.Finding(12) = 1
spades.Finding(13) = 1

You should NOT try to weight the findings vector according to some distribution function on how cards are distributed. This is probably already handled in your Bbn model...


HUGIN Expert A/S, 2008 - comments to activex@hugin.com