UNIVERSITY EXAMINATIONS: 2014/2015
ORDINARY EXAMINATION FOR THE BACHELOR OF SCIENCE
IN INFORMATION TECHNOLOGY
BIT 4405 EXPERT SYSTEMS
DATE: APRIL, 2015 TIME: 2 HOURS
INSTRUCTIONS: Answer Question ONE and any other TWO
QUESTION ONE
a) Using examples differentiate between exact reasoning and inexact reasoning
(4 marks)
b) Explain the benefits of using rules (6 marks)
c) Elaborate on the initial idea of production system as given by Post. (4 marks)
d) Discuss the need for heuristic reasoning in knowledge based systems. (6 marks)
e) Using examples differentiate between A priori knowledge and a posteriori knowledge
(6 marks)
f) Differentiate between inference and explanation (4 marks)
QUESTION TWO
a) Examine the three major participants in expert system development (9 marks)
b) Describe the recognize-act cycles as facilitated by the inference engine. (7 marks
c) Given the following rules:
R1:If corn is grown on poor soil, then it will rot.
R2:If soil hasn’t enough nitrogen, then it is poor soil
Explain how you the rules will be applied in forward chaining and backward chaining
(4 marks)
QUESTION THREE
a) Expound on the expert system development stages (12 marks)
b) Explain the features of an expert system (8 marks)
QUESTION FOUR
a) The function of a financial advisor is to help the user decide whether to invest in a
savings account, or the stock market, or both. The recommended investment depends
on the investor’s income and the current amount they have saved:
Individuals with inadequate savings should always increase the amount saved as their
first priority, regardless of income.
Individuals with adequate savings and an adequate income should consider riskier but
potentially more profitable investment in the stock market.
Individuals with low income who already have adequate savings may want to consider
splitting their surplus income between savings and stocks, to increase the cushion in
savings while attempting to increase their income through stocks
The adequacy of both savings and income is determined by the number of dependants an
individual must support. There must be at least £3000 in the bank for each dependant. An
adequate income is a steady income, and it must supply at least £9000 per year, plus 2500
dependant for each dependant
Required
a) Produce an AND-OR graph for the provided information (14 marks)
b) Write a simple post production rules for starting of a car (6 marks)
QUESTION FIVE
1. IF (Animal has hair) or (Animal drinks milk) THEN Animal is a mammal
2. IF (Animal has feathers) or ((Animal can fly) and (Animal lays eggs))THEN Animal is
a bird
3. IF (Animal is a mammal) and ((Animal eats meat) or ((Animal has pointed_teeth) and
(Animal has claws) and (Animal has forward_pointed_eyes))) THEN Animal is a
carnivore
4. IF (Animal is a carnivore) and (Animal has tawny_colour) and (Animal has
dark_spots) THEN Animal is a cheetah
5. IF (Animal is a carnivore) and (Animal has tawny_colour) and (Animal has
black_stripes) THEN Animal is a tiger
6. IF (Animal is a bird) and (Animal cannot flies) and (Animal can swim)
THEN Animal is a penguin
7. IF (Animal is a bird) and (Animal has large_wingspan) THEN Animal
Assume there are the following facts in the working memory: Jimmy has hair, jimmy has
pointed_teeth, jimmy has claws, jimmy has forward_pointed_eyes, jimmy has
black_stripes, jimmy has tawny_colour
Suppose that we want to see whether jimmy is a tiger using backward chaining.How will
it work? (20 marks)
