On Oct 10, 2007, at 7:10 AM, David Robert White wrote:
> Firstly - thanks to all those who have contributed to ECJ. I've
> been using it for a while and have found it to be a great toolkit
> to work with.
> I've recently started using the SPEA2 classes with ECJ. I have two
> queries that I need help with:
> 1. Which one of the following correctly describes the fitness
> values held in multifitness within the SPEA2MultiObjectiveFitness
> class, inherited from the MultiObjectiveFitness class:
> 0 (best) to infinity (worst)
> 0 (worst) to infinity (best)
> 0 (worst) to 1 (best)
> I know this is a basic question, but it seems to depend on where
> you look as to which answer you receive.
I think this is a documentation casualty of minor changes made to
ECJ's fitness model. I *believe* the proper answer should be 0
(worst) to infinity (better than the best). But as SPEA2 uses a
tournament selection mechanism, your fitness values can *probably* be
anything >= 0 so long as x>y if x is better than y in that objective.
> 2. Does anyone have an example that uses SPEA2, including their
> parameter files, that they could possibly share?
Rob Hubley wrote the package and can speak best here. Here's his URL: