Expert Systems

What is Expert System ?
· An expert system is a computer program that simulates the thought
process of a human expert to solve complex decision problems in
a specific domain.
• An expert system, is an interactive computer-based decision tool that
uses both facts and heuristics to solve difficult decision making problems,
based on knowledge acquired from an expert.
• An expert system is a model and associated procedure that exhibits,
within a specific domain, a degree of expertise in problem solving
that is comparable to that of a human expert.
• An expert system compared with traditional computer :
Inference engine + Knowledge = Expert system
( Algorithm + Data structures = Program in traditional computer )
The Need for Expert Systems
Expert systems are necessitated by the limitations associated with
conventional human decision-making processes, including:
1. Human expertise is very scarce.
2. Humans get tired from physical or mental workload.
3. Humans forget crucial details of a problem.
4. Humans are inconsistent in their day-to-day decisions.
5. Humans have limited working memory.
6. Humans are unable to comprehend large amounts of data quickly.
7. Humans are unable to retain large amounts of data in memory.
8. Humans are slow in recalling information stored in memory.
9. Humans are subject to deliberate or inadvertent bias in their
actions.
10. Humans can deliberately avoid decision responsibilities.
11. Humans lie, hide, and die.
Coupled with these human limitations are the weaknesses inherent in
conventional programming and traditional decision-support tools.
Conventional programs:
1. Are algorithmic in nature and depend only on raw machine power
2. Depend on facts that may be difficult to obtain