Expert SystemsExpert Systems

Chris LaJoie, Chris Panton, Chris LaJoie, Chris Panton,

and Kurt DeVaneyand Kurt DeVaney

What is an Expert System?What is an Expert System?

A system that uses human expertise A system that uses human expertise to make complicated decisions.to make complicated decisions.

Simulates reasoning by applying Simulates reasoning by applying knowledge and interfaces.knowledge and interfaces.

Uses expert’s knowledge as rules Uses expert’s knowledge as rules and data within the system.and data within the system.

Models the problem solving ability of Models the problem solving ability of a human expert.a human expert.

4 Components of an ES4 Components of an ES

1.1. Knowledge BaseKnowledge Base

2.2. Reasoning or Inference EngineReasoning or Inference Engine

3.3. User InterfaceUser Interface

4.4. Explanation Facility Explanation Facility

Interpreter

Inference

Engine

Knowledge Based Rules

Data base Context Set of facts

Natural

Language

Interface

Expert

User

Expert System StructureExpert System Structure

Knowledge BaseKnowledge Base

Represents all the data and Represents all the data and information imputed by experts in information imputed by experts in the field.the field.

Stores the data as a set of rules that Stores the data as a set of rules that the system must follow to make the system must follow to make decisions.decisions.

Knowledge AcquisitionKnowledge Acquisition

Expert System

Knowledge Engineer

Human Expert

Inference EngineInference Engine

Asks the user questions about what Asks the user questions about what they are looking for.they are looking for.

Applies the knowledge and the rules Applies the knowledge and the rules held in the knowledge base.held in the knowledge base.

Appropriately uses this information Appropriately uses this information to arrive at a decision. to arrive at a decision.

• Expert System designed to help users complete tax returns

http://youtube.com/watch?v=5b7KhvQSNcY

Turbo TaxTurbo Tax

User InterfaceUser Interface

Allows the expert system and the Allows the expert system and the user to communicate.user to communicate.

Finds out what it is that the system Finds out what it is that the system needs to answer.needs to answer.

Sends the user questions or answers Sends the user questions or answers and receives their response. and receives their response.

Explanation FacilityExplanation Facility

Explains the systems reasoning and Explains the systems reasoning and justifies its conclusions. justifies its conclusions.

Does anyone know any examples Does anyone know any examples of expert systems used in everyday of expert systems used in everyday

life?life?

The Patriot Missile The Patriot Missile

It does all the work of the stinger and It does all the work of the stinger and sidewinder but faster, more efficient, sidewinder but faster, more efficient, from a longer range and without the from a longer range and without the need an expert. need an expert.

PATRIOT VS. SCUD PATRIOT VS. SCUD MissileMissile

http://youtube.com/watch?http://youtube.com/watch?v=T68K3Twrm20&feature=relatedv=T68K3Twrm20&feature=related

Medical Diagnosis & Expert Medical Diagnosis & Expert SystemsSystems

Pathology is the study of the origin, Pathology is the study of the origin, nature, and course of diseases.nature, and course of diseases.

Pathology reports explain the Pathology reports explain the outcomes of tests on the patient and outcomes of tests on the patient and the diseases various information.the diseases various information.

Pathologists were in need of a Pathologists were in need of a comprehensive interpretative service comprehensive interpretative service to help them interpret these reports.to help them interpret these reports.

PEIRSPEIRS

PEIRS (Pathology Expert PEIRS (Pathology Expert Interpretative Reporting System) was Interpretative Reporting System) was created as a user-maintained expert created as a user-maintained expert system for automating the system for automating the interpretation of chemical pathology interpretation of chemical pathology reports.reports.

The system uses over 2500 rules to The system uses over 2500 rules to generate interpretive comments on generate interpretive comments on the reports.the reports.

Expert System Application in Expert System Application in Everyday LifeEveryday Life

http://expertise2go.com/webesie/wine/http://expertise2go.com/webesie/wine/

Ethical ImplicationsEthical Implications

Do you want to put a decision about Do you want to put a decision about your life in the hands of a computer?your life in the hands of a computer?

When do you think you’d trust a When do you think you’d trust a computer’s judgment over a doctors?computer’s judgment over a doctors?

Problems with Expert SystemsProblems with Expert Systems

There is no expert in the fieldThere is no expert in the field The expert is unable to communicate The expert is unable to communicate

his/her ideashis/her ideas The expert is unwilling to communicate The expert is unwilling to communicate

his/her ideashis/her ideas The expert is not availableThe expert is not available Must have all information on a subjectMust have all information on a subject Can all the testing be accomplished?Can all the testing be accomplished? User acceptanceUser acceptance

What is a Decision Support What is a Decision Support System?System?

An information system that utilizes An information system that utilizes analytical modeling and helps analytical modeling and helps

executives make strategic decisionsexecutives make strategic decisions

DSS is user-driven and rely on the DSS is user-driven and rely on the knowledge possessed by its userknowledge possessed by its user

DSS vs. Expert SystemsDSS vs. Expert Systems

DSS uses analytical modeling for DSS uses analytical modeling for decision makingdecision making

Expert Systems are interactive and Expert Systems are interactive and make decisions for youmake decisions for you

Advantages of Expert SystemsAdvantages of Expert Systems

Can be simple to useCan be simple to use Efficient resultsEfficient results Accurate resultsAccurate results Adaptation and adjustments to Adaptation and adjustments to

changing conditionschanging conditions Cost effectiveCost effective

Questions?Questions?