F9 Benchmark where Hill Climber does better than differential evolution

Figure 9 from:
Evolving Problems to Learn about Particle Swarm and other Optimisers W. B. Langdon and Riccardo Poli in Proceedings of the 2005 IEEE Congress on Evolutionary Computation, CEC 2005, volume 1, pp81-88, 2-5 September, Edinburgh, UK.
paper.
Java code
gnuplot script

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W.B.Langdon 20 Feb 2006