SCXT 350

Hour Exam #2

Name_______________________________________

Friday, Oct. 20

100 pts.

1. (10 pts.) Give a brief description of Marr's three levels of explanation of an information processing system.

2. (10 pts.) Our discussion over the past few weeks has centered around knowledge representation and problem solving (viewed as search). At what level of explanation is this, and why?

3. (15 pts.) Reconsider the Turing Test. Imagine that you are sitting at a terminal/workstation/computer engaged in casual conversation via typewritten questions and responses with another user of the computer network. Briefly outline the behavior of your correspondent using Marr's levels of explanation.

For the next few exercises, consider the problem space of the wine-pouring problem:

4. (15 pts.) We have discussed problem solving through the use of operators and states. Give brief definitions of those terms. What role do preconditions and postconditions play?

5. (15 pts.) Give a brief description of depth-first search, illustrating your response by tracing (giving in order) some of the steps that might be taken in solving the wine-pouring problem above. Feel free to include states not in the portion of the diagram given above.

6. (15 pts.) Give a brief description of breadth-first search, illustrating your response by tracing some of the steps that might be taken in solving the wine-pouring problem above.

7. (10 pts.) What is a heuristic? Suggest a heuristic for the wine-pouring problem.

8. (10 pts.) What is means-ends analysis, and what do we mean by saying that it is a "divide and conquer" problem-solving strategy?