abstract = "Multi-objective optimisation is applied to encourage
the effective use of state variables in car controlling
programs evolved using Genetic Programming. Three
different metrics for measuring the use of state within
a program are introduced. Comparisons are performed
among multi- and single-objective fitness functions
with respect to learning speed and final fitness of
evolved individuals, and attempts are made at
understanding whether there is a trade-off between good
performance and stateful controllers in this problem
domain.",
notes = "CEC 2007 - A joint meeting of the IEEE, the EPS, and
the IET.