Page 204 - DCAP310_INTRODUCTION_TO_ARTIFICIAL_INTELLIGENCE_AND_EXPERT_SYSTEMS

Introduction to Artificial Intelligence & Expert Systems

Notes Recognition of the intended request can be achieved by matching against key words in a
template containing “low-calorie” and ignoring other words except, perhaps, negative
modifiers.
The RETE is a directed, acyclic, rooted graph. Each path from the root node to a leaf in the
tree represents the left-hand side of a rule. Each node stores details of which facts have
been matched by the rules at that point in the path.
A graph is a collection of points called vertices, some of which are connected by line
segments called edges.
The match fails if the patterns differ in any aspect. For example, a match between the two
character strings acdebfba and acdebeba fails on an exact match since the strings differ in
the sixth character positions.

10.8 Keywords

Expert System: An expert system is a computer system that emulates the decision-making ability
of a human expert.
Fuzzy Logic: Is a form of many-valued logic or probabilistic logic; it deals with reasoning that
is approximate rather than fixed and exact.

LISP: It is a family of computer programming languages with a long history and a distinctive,
fully parenthesized Polish prefix notation.
Probabilistic Logic: It is to combine the capacity of probability theory to handle uncertainty
with the capacity of deductive logic to exploit structure.
RETE Algorithm: The RETE algorithm is an efficient pattern matching algorithm for implementing
production rule systems.

10.9 Review Questions

1. What is pattern matching?
2. What are the different matching measurements for matching?
3. How is pattern matching important in real life?

4. Explain Prediction by partial matching.
5. Describe fuzzy matching algorithms.
6. Explain image processing.

7. Write the different probabilistic measures.
8. How does AI help in pattern matching?
9. Describe the working of any real life expert system.
10. Write the RETE algorithm.

Answers: Self Assessment

1. True 2. True

3. True 4. False
5. True 6. False

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