Exercises

1. Construct Semantic Net representations of the following:
   1. Dave is Welsh, Dave is a Lecturer.
   2. Paul leant his new Frank Zappa CD to his best friend.
2. Find out how the SNePS system aims to improve the expressiveness of semantic nets.
3. Represent the following in a Semantic Net and Comment on how the SNePS system helps.
   1. Mike and Mary's telephone number is the same.
   2. John believes that Mike and Mary's telephone number is the same.
4. Represent the following in partitioned semantic networks:
   1. Every player kicked a ball.
   2. All players like the referee.
   3. Andrew believes that there is a fish with lungs.
5. Simplify Fig. 16 that represents parent(x) : baby(y) loves(x,y)

   so that we can express variables as existentially qualified variables and express the event of love having an agent p and receiver b for every parent p.

6. Pick a problem area and represent the knowledge in frame based system.
7. Devise algorithms that enable reasoning with frames. Discuss how
   1. Inference through inheritance can be achieved.
   2. Matching can be achieved.
8. What are the advantages of a frame based knowledge representation?
9. What problems do you envisage a a frame based knowledge representation having? Give examples of knowledge hard to represent in a frame. How could some problems be overcome?

   HINT: address issues to do with semantics, inheritance, expressiveness.

10. What programming languages would be suited to implement a semantic network and frames?