Hybrid Metaheuristics: 5th International Workshop, HM 2008, Malaga, Spain, October 8-9, 2008 Proceedings

"You see, I have a lot of special knowledge which I apply to the problem, and which facilitates matters wonderfully," says Sherlock Holmes to Dr. Watson in A Study in Scarlet by Arthur Conan Doyle. The knowledge exploited to tackle di?cult problems is probably the main theme of the papers selectedfor this ?fth editionofthe InternationalWorkshoponHybridMetaheuristics. Indeed,inmost of the papers a speci?c combination of metaheuristics and other solving te- niques is presented for tackling a particular relevant constrained optimization problem, such as ?ber optic networks, timetabling and freight train scheduling problems. The quest for solvers which can successfully and e?ciently handle relevant problems is the main motivation for research in metaheuristics: it is important to keep this in mind so as to clearly state our research goals and methodology. The question arises as to what is the de?nition of relevant pr- lems and a possible answer is that any useful and even just interesting or funny problem can be considered as scienti?cally relevant. The research goal of solving relevant problems does not require practitioners to assemble some software code and, with a little faith in alchemy, hope that the outcome is a reasonably good solution. On the contrary, this research must be grounded on a scienti?c method and on technological skills. That is why it is so important to support the assessment of an algorithm's performance with a sound methodology.