Transcript 511 - Data, Information, Knowledge and Processing

Expert Systems
Learning Objectives:
By the end of this topic you should be able to:
• explain what is meant by an expert system
• describe the components of an expert system
• describe the applications of an expert system
Expert Systems
In everyday life:
Expert Systems
In everyday life:
• humans interpret information to gain knowledge
Expert Systems
In everyday life:
• humans interpret information to gain knowledge
• this knowledge is used as the basis for making decisions
Expert Systems
In everyday life:
• humans interpret information to gain knowledge
• this knowledge is used as the basis for making decisions
An expert system is:
Expert Systems
In everyday life:
• humans interpret information to gain knowledge
• this knowledge is used as the basis for making decisions
An expert system is:
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a computer program, used to help with a decision making process
Expert Systems
In everyday life:
• humans interpret information to gain knowledge
• this knowledge is used as the basis for making decisions
An expert system is:
•
a computer program, used to help with a decision making process
•
aka rules-based system, knowledge system
An Expert System is:
An Expert System:
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is a computer program
is made up of a set of rules
analyses information about a specific type of problem.
trys to solve a problem in the same way as a human expert
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has a narrow range of expertise
gives answers to questions
asks questions based on previous responses
can show how it reached conclusions
can learn from experience (heuristic)
• is based on probabilities, not certainties
• based on research into Artificial Intelligence (AI)
Expert System - Definition
• has three components:
Expert System - 3 components
• knowledge base
– set of rules
– consists of If...Then… rules
– e.g. IF it is raining THEN I need to take an umbrella with me
Expert System - 3 components
• knowledge base
– set of rules
– consists of If...Then… rules
– e.g. IF it is raining THEN I need to take an umbrella with me
• inference engine
– evaluates data against the knowledge base
– to provide a conclusion
Expert System - 3 components
• knowledge base
– set of rules
– consists of If...Then… rules
– e.g. IF it is raining THEN I need to take an umbrella with me
• inference engine
– evaluates data against the knowledge base
– to provide a conclusion
• user interface
– displays questions to be completed by the operator
– displays conclusions as output
Examples of Expert Systems
Examples of Expert Systems
• weather forecasting
Examples of Expert Systems
• weather forecasting
• fault diagnosis
– electrical goods, cars
Examples of Expert Systems
• weather forecasting
• fault diagnosis
– electrical goods, cars
• medical diagnosis
– diagnose blood infections, identify tumours
Examples of Expert Systems
• weather forecasting
• fault diagnosis
– electrical goods, cars
• medical diagnosis
– diagnose blood infections, identify tumours
• facial recognition
Examples of Expert Systems
• weather forecasting
• fault diagnosis
– electrical goods, cars
• medical diagnosis
– diagnose blood infections, identify tumours
• facial recognition
• careers advice
Examples of Expert Systems
• weather forecasting
• fault diagnosis
– electrical goods, cars
• medical diagnosis
– diagnose blood infections, identify tumours
• facial recognition
• careers advice
• credit scoring
– identifying whether or not an individual should be granted credit
Examples of Expert Systems
• weather forecasting
• fault diagnosis
– electrical goods, cars
• medical diagnosis
– diagnose blood infections, identify tumours
• facial recognition
• careers advice
• credit scoring
– identifying whether or not an individual should be granted credit
• financial planning
– what if we …..?”