Empirical Testing of a Weight Constraint Rule Based Configurator

1&2 Helsinki University of Technology, Dept of Computer Science and Eng., 1 Software Business and Engineering Institute, P.O.B. 9600, FI-02015 HUT 2 Lab. for Theoretical Computer Science, P.O.Box 5400, FI-02015 HUT 1&2 {Juha.Tiihonen, Timo.Soininen, Ilkka.Niemela, Reijo.Sulonen}@hut.fi Abstract. In this paper we first describe a configurator implementation based on a practically important subset of a synthesized ontology of configuration knowledge. The underlying configuration modeling language has been provided with a declarative semantics by mapping it to weight constraint rules, a form of logic programs. Three issues important for efficiency of the implementation are addressed: off-line compilation of configuration models, limiting a configuration to a finite size in a semantically justified way, and breaking symmetries in the set of configurations. The second part of the paper takes a step in the direction of thorough empirical testing of configurators. We define a relatively modeling-languageindependent method for testing configurators based on the idea of simulating a naïve user inputting random requirements to a configurator. We test the configurator empirically on batch-mode sales configuration of four real products with progressively larger and thus more restricting sets of random user requirements. The results indicate that our configurator is efficient enough for practical use.