Presentation on theme: "Have you downloaded and registered Exsys‘s CORVID expert system software ?"— Presentation transcript:
have you downloaded and registered Exsys‘s CORVID expert system software ?
Expert Systems our example a Credit Union – simulating an experienced loan officer processing loan applications
the rules : variables the logic : "IF …. THEN…" "SINCE …. I KNEW THAT…" may involve several conditions that are combined the command : execute the logic
case number loan purpose ability to repay past payment record loan officer's decision 1frivolousgood GRANT 2frivolousgoodslowGRANT 3frivolousgoodpoorDENY 4frivolousbadgoodDENY 5frivolousbadslowDENY 6frivolousbadpoorDENY 7necessitygood GRANT 8necessitygoodslowGRANT 9necessitygoodpoorGRANT 10necessitybadgoodGRANT 11necessitybadslowGRANT 12necessitybadpoorDENY 13luxurygood GRANT 14luxurygoodslowGRANT 15luxurygoodpoorDENY 16luxurybadgoodDENY 17luxurybadslowDENY 18luxurybadpoorDENY The tree diagram makes it easier to see the overall structure of the rules. In CORVID, the logic of a system is built in Logic Blocks which hold the tree diagrams and other logical information. nodes
Ability to Repay Past Payment Record good bad loan purpose GRANT good slow DENY poor GRANT luxury frivolous necessity poor DENY good slow necessity luxury frivolous DENY GRANT nodes
the main CORVID working window please start a new system and save file extension:.cvd
this window provides a wide range of ways to control how a variable is defined, used and asked of the system user.
variables fundamental building blocks for the CORVID expert system three types of variables static list variables numeric variables confidence variables
in our example:static list variables loan purpose ability to repay past payment record
to create a new CORVID variable new variables: name – unique, short, descriptive type – static, numeric, confidence
examples of logic: IF it is raining THEN wear a raincoat. IF the car will not start AND the gas gage is on empty THEN the car is out of gas. SINCE the light was on I KNEW the computer was getting power. SINCE it is Saturday AND it is sunny I KNEW Fred was probably playing golf.
bottom left: if / and ‘add’ ‘add to block’ pop-up dialogue box choose a variable select a value ‘add to list’ ‘done’
for the next node : repeat value selection for the next variable and the last variable
now for the final result, the decision: ‘THEN assignment nodes’ dialogue box
select either grant or deny value to assign to [grant] : [grant] = 100 done
please set up the logic blocks for all the loan officer’s decisions listed on the handout
command block C The Logic Blocks in a system tell it HOW to do something. The Command Blocks tell it WHAT to do and WHEN. control commands operational commands
use a DERIVE command to run the rules and logic