Learning rewrite rules to improve plan quality

Considerable planning and learning research has been devoted to the problem of learning domain specific search control rules to improve planning efficiency. There have also been a few attempts to learn search control rules that improve plan quality but such efforts have been limited to state-space planners. The reason being that most of the newer planning approaches are based on plan refinement. In such planners, informa-tion about the current state of the world that is re-quired to evaluate a complex quality metric is simply not available during planning. An alternative technique is planning by rewritingthat suggests first generating an initial plan using a refinement planner and then using a set of rewrite-rules to transform it into a higher qual-ity plan (Ambite ~ Knoblock 1997). Unlike the searc