Generalised Means-End Analysis

The problem solving strategy in the previous model is known as means-ends analysis (MEA). In general, MEA involves locating the largest difference between current and goal state, and selecting an operator to eliminate this difference. Using MEA on a specific problem requires identifying an appropriate distance measure for differences;identifying operators that can eliminate differences.Most people seem to have access to this general strategy.

Why didn't the subject use MEA from the outset? She may have assumed a simpler solution strategy (selection without search) was sufficient.She may have lacked the knowledge of the problem space needed to perform MEA (operators and differences that they can be used to eliminate).

Hypothesis: During her first attempt, the subject acquired an understanding of how to decompose the problem into subgoals (corresponding to moving disks of successively smaller sizes to the right peg) Evidence: Explicit mention of subgoals became more common as she gained experience with the task

Goal-directed search does NOT use a general purpose strategy. Rather, it uses a specialisation of MEA appropriate to the Tower of Hanoi problem.

What is MEA?

Why didn't the subject use MEA from the outset?