CBR Exercise

• The May 2004 Exam (like all of the exams) had a question on CBR systems.
• a) A case based expert system has been designed to select the correct shrub for a garden. The system starts with four cases. The first case is a 5x10 meter garden, with 3 other shrubs; the correct shrub to add to this is a Japanese Maple. The second case is a 10x10 meter garden with no other shrubs; the correct shrub to add is a Lilac. The third case is a 9x9 meter garden with 5 other shrubs; the correct shrub to add is a rose bush. The fourth case is a 5x5 meter garden with 2 other shrubs; and you should not add another shrub. How do you represent the cases?
• b) Using a straight-forward distance metric, calculate which shrub to use for a garden that is 7x7 and has no shrubs. Give your distances.
• c) The system chooses a Japanese maple for a 8x15 garden with 12 shrubs. A human expert says that the correct answer is no shrub. Discuss different ways to modify your system to account for this, and compare the different approaches.