THE UNIVERSITY OF SUSSEX CG019

BA & LLB FIRST YEAR EXAMINATION 2002

COGNITIVE MODELLING

Wednesday 19th June 2002 18.00 - 19.30

Candidates must attempt TWO questions
Each question is worth 25 marks.

1. In the context of the Feed Forward Neural Network program for distinguishing words from non-words that you have studied:
   1. Describe the overall structure of the network. (4)
   2. With the aid of a diagram, explain the process by which any of the hidden nodes fire or not. (5)
   3. Explain the process by which the network can be trained. (8)
   4. Discuss the strengths and weaknesses of this network program as a model of human ability to distinguish words from non-words. (8)

2. 1. In the context of the Young and O'Shea Production System that you have studied:
      1. Explain how the system models children's subtraction behaviour. Your answer should also explain what aspects of children's subtraction behaviour are being modelled and which are not. (8)
      2. Describe two ways in which errors are modelled. (4)
      3. Describe two ways by which learning could be modelled. (4)
   2. Describe how either ACT or SOAR has been used to model some aspect of cognition. (9)

3. In the context of the Blocks World understanding program that you have studied:
   1. Sometimes the simulated robot is unable to carry out a command you type in. Give three different reasons why a correctly spelled and grammatical command may fail to be carried out, and explain which representation(s) would need to be changed to fix this in each case. (12)

      Please Turn Over

   2. How is the robot's knowledge of the Blocks World and of actions it can carry out in that world modelled? (6)

   3. Compare and contrast, as cognitive models, the Blocks World language understanding program and its robot with the robots exemplified by Braitenberg. (7)