Describing Problem Solving Methods using Anytime Performance Profiles

Annette ten Teije & Frank van Harmelen

Traditional selection criteria for Problem Solving Methods (PSMs) from libraries concentrate solely on the functionality of these methods, and ignore their computational performance. We propose the use of anytime performance profiles to describe the computational behaviour of problem solving methods, and to use these as additional selection criteria when selecting methods from a library. A performance profile describes how the quality of the output of an algorithm gradually increases as a function of the computation time. Such anytime descriptions of problem solving methods are attractive because they allow a trade-off to be made between available computation time and output-quality. It turns out that many problem solving methods found in the literature have a natural anytime behaviour, which has remained largely unexploited until now.

In this paper we propose an axiomatic description of performance profiles. Furthermore, in order to make our proposal feasible for library builders, we give guidelines on how to organise such axiomatic descriptions. Finally, we apply our proposal to a number of realistic problem-solving methods, namely hierarchical classification (used in MDX), parametric design (methods from XCON and VT), and consistency-based diagnosis (the GDE-method).