Phase Transitions of Plan Modification in Conformant Planning

TL;DR

This paper investigates phase transitions in plan modification for conformant planning, revealing a threshold based on operator density that determines solvability in most cases.

Contribution

It identifies a critical operator density threshold that predicts the success of plan modification in conformant planning problems.

Findings

Below the threshold, most problems cannot be solved with plan modification.

Above the threshold, most problems can be solved with plan modification.

An experimental threshold of operator-to-proposition ratio separates solvable and unsolvable regions.

Abstract

We explore phase transitions of plan modification, which mainly focus on the conformant planning problems. By analyzing features of plan modification in conformant planning problems, quantitative results are obtained. If the number of operators is less than, almost all conformant planning problems can't be solved with plan modification. If the number of operators is more than, almost all conformant planning problems can be solved with plan modification. The results of the experiments also show that there exists an experimental threshold of density (ratio of number of operators to number of propositions), which separates the region where almost all conformant planning problems can't be solved with plan modification from the region where almost all conformant planning problems can be solved with plan modification.