SEKE 2012 Proceedings - Knowledge Systems Institute

Three rules match with the expression in working
memory: Rule 1, Rule 2 and Rule 3. I f we resolve
conflicts in favour of the lowest-numbered rule, then
Rule 1 will fire. This causes X to be bound to the value
‘Customer belongs to Bank1’ and the premise of Rule 1
to be placed in working memory (Fig 3). The system has
thus chosen to explore the possible hypothesis that the
customer belongs to Bank 1. Another way to look at this
is that the system has selected an ‘Or’ branch in the And
/ Or graph in Fig 1.
We also note that there are two premises to Rule 1, both
of which must be satisfied to prove the conclusion true.
These are ‘And’ branches of the search graph
representing a d ecomposition of the problem (finding
whether the customer belongs to Bank 1) into two sub
problems (finding whether the PhoneNo matches with
PhoneNo in Bank1 Knowledge Base, and Address
Information matches with Address in Bank1 Knowledge
Base). We m ay then fire Rule 4, whose conclusion
matches with ‘Address Information matches with
Address Information in Bank1 Knowledge Base’
causing its premises to be placed in working memory as
in Fig 4.
At this point, there are three entries in working memory
that do not match with any rule conclusions. Our expert
system will, in this situation, query the user customer
directly about these sub goals. If the customer confirms
all three of these as true, the expert system will have
successfully determined that the customer belongs to
Bank1. In this case, the use case will return the balance
of the customer from Bank1. In our example, had we
failed to determine that the customer belongs to Bank1,
we would have needed to back up to the top level and try
Rule 2 instead.
Let us now consider a tr ace of the reasoning process.
Suppose our expert system has an explanation facility,
and let us assume that the consultation has reached the
stage represented by the working memory configuration
in Fig 4.
The following dialogue begins with the computer asking
the customer about the goals present in the working
memory.
Is your Phone Number 12345678?
Yes
Is your Address po_box_19_AB_Avenue_Kolkata?
Yes
Is your Name prakash_kumar?
Why
Here the system responds with a literal presentation of
the rule under question.
It has been established that:
The Address Information matches with that in Bank1
Knowledge base,
Therefore if
The Name matches with that in Bank1 Knowledge base
Then you are a customer of Bank1.
Following the above trace, the deposit of c ustomer
would be displayed.
Because the customer answered yes to the first two
questions, Rule 4 was able to fire, verifying the second
premise of Rule 1. When the ‘why’ query was made, the
system was trying to solve the first premise of Rule 1. It
is to be noted that the explanation for the systems
behavior is just a r estatement of the current rule under
consideration. However, this provides an adequate
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