abstract = "To investigate the fundamental causes of bloat, six
artificial random binary tree search spaces are
presented. Fitness is given by program syntax (the
genetic programming genotype). GP populations are
evolved on both random problems and problems with
``building blocks''. These are compared to problems
with explicit ineffective code (introns, junk code,
inviable code). Our results suggest the entropy random
walk explanation of bloat remains viable. The hard
building block problem might be used in further
studies, e.g. of standard subtree crossover.",
notes = "C++ code at ftp://ftp.cs.ucl.ac.uk/wblangdon/gp-code/
http://www-syntim.inria.fr/fractales/PPSN2000/program.html#108
PPSN'2000