-*- mode:Text -*-
Copyright 1992 Patrick H. Winston.  All rights reserved.
Version 1.1, transferred from master disk on 21 Jan 93
 
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PURPOSE

Provides program support for Chapter 8, Rules, Substrates, and
Cognitive Modeling.  Illustrates SOAR's preference system using a
highway net.

REMARKS

This search procedures provided work by installing preference
links and by using SOAR's preference mechanism on those links.
Note that there is no recourse once an impasse is encountered;
accordingly, if there are candidates for the next current state,
one of those candidates is picked at random.

PERFORMANCE EXPERIMENT 1

Examine the file prefer.exp.  Run the search experiments by
typing the following command to your lisp system:

(load "prefer.exp")

Alternatively, evaluate each Lisp expression in the file one at a
time, noting what each does.

PERFORMANCE EXPERIMENT 2

Run the search procedures with other initial and destination
cities.

SMALL-SCALE LISP PROJECT

Implement hill climbing and best-first search varients.