Question

Complete exercises 5.A.   As part of your assignment, provide a response IN YOUR OWN WORDS to the following questions.

Which of the following rules are syntactically invalid in propositional definitive clause logic, and why? (Assignment part A)

bikeCrashed ← cycledDrunk

goByBus ∨ goByCar ← bikeBroke

goByBus ← ¬haveGas ∨ bikeBroke

In propositional definite clause logic (PDCL),

What is an atom? Give the definition and an example from a domain of your choice. (Assignment part B)

What is a body? Give the definition and an example from a domain of your choice. (Assignment part C)

What is a definite clause? Give the definition and an example from a domain of your choice. (Assignment part D)

What is a knowledge base? Give the definition and an example with four clauses from a domain of your choice. (Assignment part E)

What is an interpretation of a knowledge base KB? Give the definition and an example for your KB. (Assignment part F)

What is a model of a knowledge base KB? Give the definition and an example for your KB. (Assignment part G)

Rubric

For each part of the assignment (A-G) rate the completeness on a scale of 1 – 5 where one indicates that the question was either not answered or the answer did not respond to the question to 5 where there was a complete response to the question.

Answer 1

PART A) bikeCrashed<- Cycleddrunk

The rules bikecrashed<- Cycleddrunk is correct rule as it is of the form a<-b where a is the atom and b is the body. The atom is starting with small letter b as bikecrashed so this rule is syntactically valid.

2)gobyBus v gobycar <- bikebroke

The clause a<-b is valid if the head of clause a is atom and b is body but here the head of clause is body b (gobyBus v gobycar) so this rule is invalid in propositional definitive clause logic.

3)goby bus<-~havegas v bikebroke

The atom a=gobybus. and body =~havegas V bikebroke

The above clause is sytactically invalid because clause body cannot be connected by  V(union) and (~) operations. It can only be connected by intersection.

PART B) An atom is the symbol which starts with lowercase letters for example bird_eats_fruit ,apple_is_red these all are symbols which start with lowercase letters.

PART C) A body is an atom or of the form where B1 and B2 represents the bodies. For example:

apple_is_rotten bird_eats_apple is a body, student_are_happygo_to_picnic are examples of body.

PART D) A definite clause is a rule of the form

h<-b where h is the atom and b is the body For example:

student_is_succesful <- student_work_hardstudent_is_motivated

neha_sleeps_in_room <- night_time light_is_off

PART E) knowledge base is a set of definite clauses. knowledge base store information in form of rules  and clauses. Example of knowledge base which contain four clauses are-

student_are_happy

apple_is_fruit

student_are_succesful <- student_study_hard student_are_motivated

bird_eats_fruits

PART F) The interpretation of the knowledge base is done by assigning the truth value to each atoms in every clauses.The values of atoms can be true or false. The interpretation of above knowledge base is

student_are_ happy =false

apple_is_fruit=true

student_study_hard=true

student_are_successful=true

student_are_motivated=false

bird_eats_fruits=true

PART G) The model of knowledge base is the interpretation in which all clauses are true .The model of above knowledge base contains all those clauses in which truth value is true.

apple_is_fruit=true

student_study_hard=true

student_are_successful=true

bird_eats_fruits=true