## Expert Systems

Some of the following exercise material was taken from the ESHELL User Manual from Terry Dwyer. Exercises are adapted to suit ESBuilder Web from McGoo Software.

1. Given the following tree:

use ES-Builder Web to construct a corresponding Expert System. Interrogate your expert system to ensure it makes the correct conclusions.

2. PRIMATE-ES: We can classify various representative members of families in the Sub-order Anthropod by using external characteristice as follows:

• MAN : no tail, big toe not opposable, thumb opposable
• APES: no tail, big toe and thumb opposable
• OLD WORLD MONKEYS: have a tail, big toe and thumb opposable
• MARMOSETS: a long tail, big toe opposable, thumb not opposable
• NEW WORLD MONKEYS: Long tail, big toe and thumb opposable

Using ES-Tree Builder, construct a valid tree containing the attributes, values and conclusions contained in the information above. Print this out for verification by your teacher. Save your tree on your H: drive and call it PRIMATES.

Using ES-Builder, implement your decision tree and interrogate it to ensure it is functioning correctly. Save your expert system on your H: drive using the name PRIMATES

3. Given the following:

Diamond has a specific gravity between 3 and 3.8, is of hardness 10 and has a cubic crystal system.
Topaz has a specific gravity between 3 and 3.8, a hardness of 8 and has an orthorhombic crystal system
Quartz has a trigonal crystal system, hardness 9 and a specific gravity below 3
Sapphire has a trigonal crystal system, hardness 9 and a specific gravity over 3.9

Construct a valid Tree that captures the above information. you may choose to construct 'ranges' of values to cope with attributes that do not have discrete values. Print out your tree for teacher verification. Save your tree on your H: drive.

Create a corresponding expert system, using ES-Builder to correctly implement the tree, test it and save it to your H: drive.

4. Asthma is generally identified by the symptoms of wheezing and difficulty in breathing. Asthma has a number of causes with pollen and animal hairs being the main ones. A prevention is to avoid the allergens and a bronchodilator and shots being the treatments.

Hay fever is generally identified by sore and itchy eyes together with a runny, stuffy nose. Pollen is the major cause and prevention is limited to having shots before the season that produces the pollen. A treatment is antihistamine tablets.

Excema is generally identified by a rash on the hands, face and/or neck together with scaly skin. Major causes are milk, flour, eggs, nuts, shellfish and food acids. Antihistamine is a treatment and the best prevention is to adjust the diet.

Develop a tree that summarises the above afflictions. Save and print your tree for teacher verification. Use your tree to generate and save an Expert System, and interrogate it to ensure it is working correctly.

Note: for this exercise, you will neet to decide what are attributes, what are values and what are conclusions that this system could make - there are a few different systems possible, depending on how you approach the problem.

5. If an expert system contains an error which results in damage of one kind or another, who is responsible? What if damage of some kind is caused by erroneous advice from a human expert which could have been prevented by the use of an available expert system?

wonko@wonko.info