Expert Systems

Question 1

what are expert systems?

Answer 1

its a knowledge based systems, that is an application of artificial intelligence. an expert system is almost always used in narrow field of knowledge

Question 2

what is the field of knowledge called?

Answer 2

the knowledge domain of the system

Question 3

what are the key components of expert systems?

Answer 3

to create an expert system a subject experts team of programmers and technical experts are required

expert system is an experienced practitioner in particular field e.g. medical specialist

the initial stage of building the expert system is known as knowledge acquisition

knowledge of human expert is programmed and represented as rules and facts- result is the creation of knowledge basis. it can be stored as a series of IF-THEN-ELSE rules

Question 4

what are the two types of knowledge bases in expert systems?

Answer 4

factual

heuristic

Question 5

what is factual knowledge?

Answer 5

factual information acquired by the knowledge engineers from human experts, relating to subject domain- this information would be widely agreed

Question 6

what is heuristic knowledge?

Answer 6

captures information about accurate judgement and ability to estimate and evaluate. such rules are not derived from logic alone but from personal experience- described as rule of thumb.

designed to work with uncertainty and stimulate producing decisions based on experience

Question 7

what is the name of the consulting system put in place after knowledge base has been created?

Answer 7

inference engine

the software interrogates the knowledge base and draws inferences and conclusions based on rules stored about subject domain

it poses questions to user and uses answers provided by user to determine suitable response

Question 8

what is a user interface?

Answer 8

it allows a user to communicate with the system. requests for information or advice are passed from the user interface to interface engine. the request is processed by inference engine which applies rules to the knowledge base and returns a response to the user

Question 9

what is a shell?

Answer 9

its a piece of software which contains the structure for creating an expert system. it is described as an empty system without knowledge base
, the creator can enter appropriate rules and facts to generate an expert system

Question 10

applications of fuzzy logic

Answer 10

lower-level machine control, especially consumer products

fuzzy logic is integrated into home appliances such as- vacuum cleaner, microwave ovens and video cameras

e.g. anti-lock brake system in a car

the control rules contains parameters such as brake pressure and break temperature

Question 11

what are the examples expert systems?

Answer 11

medicine

care engine fault diagnosis

life insurance

Question 12

medicine expert system enable situations where:

Answer 12

they have to decide who gets treated first

GP knowledge may be out of date or may not be aware of new modern drug

may not be aware of new rare condition and therefore don’t recognise it or how to deal with it

they may be unsure of diagnosis and want to check diagnosis with someone with more experience

Question 13

how would the medicine expert system work?

Answer 13

the knowledge base would contain medical information, the patients symptoms would be used as the query and the advice would be diagnosis of the patients illness

Question 14

how would the car fault manufacturer expert system work?

Answer 14

the information is stored on a computer which can be plugged into the car to determine the nature of the fault. the system will recommend how to fix the problem

Question 15

what are the factors when calculating insurance prices

Answer 15

age

gender

smoking status

health

Question 16

how does life insurance expert system work?

Answer 16

the system will present questions to the user based on their responses, through the use of inference engine, interrogate the knowledge base to produce a cost for the premium based on the individual response of the user

human experts in the form of consultants are required. the consultants will be questioned by the knowledge engineers. they explain how they make the decisions about life insurance applications with information/data or rule of thumb

Question 17

benefits of using expert system

Answer 17

expert advice is always available

knowledge of experts can be recorded and used before they move on

can be used as a training aid to increase the expertise of staff

makes rational decisions without emotional overhead

doesn’t get tired

can perform tasks much faster than human experts

can quickly identify faults in equipment

very accurate

more cheaper

expert system can be harnessed with combination of lots of experts- one expert shared globally

Question 18

limitations of using expert system

Answer 18

can make mistakes and don’t learn from them

risk is over reliance on technology- may become deskilled

work well when problems are specific and well defined. less suited to less predictable decisions

human advisor may take into account special circumstances which would be overlooked

can give its reasons for a decision- but cannot be questioned further

every scenario cannot be programmed- errors may be possible

Question 19

what is the structure of expert system?

Answer 19

knowledge acquisition> knowledge base> inference engine>
user interface>use