Specifying action persistence within XCS
Alwyn M. Barry · 2000
In investigating the Consecutive State Problem within XCS (Barry, 1999) it was suggested that a possible solution lay in allowing the XCS to persist with a single action over the aliased states. It was shown that this technique was sufficient to overcome the Consecutive State Problem as long as mechanisms were also provided which prevented the persistent application of 'Null Actions'. An alternative solution based on the work of Cobb and Grefenstette (1991) was discussed which sought to extend the action of each classifier so that each classifier could specify the duration that the action should be applied for. It was noted that this was an inadequate solution for the Consecutive State Problem because XCS would still explore the possibility of an action which persisted into but not beyond the aliased states. This work now applies these ideas to a number of non-aliased multiple step environments. It demonstrates that, given a suitable exploration strategy, action pe...