abstract = "The genetic programming (GP) evolutionary process
typically introduces a large amount of redundancy and
unnecessary complexity into evolved programs. Quick
growth of redundant and functionally useless sections
of programs can quickly overcome a GP system,
exhausting system resources and causing premature
termination of the system before an acceptable solution
can be found. Rather than implicitly controlling the
redundancy and code growth/bloat as in most of the
existing approaches, this paper investigates an
algebraic simplification algorithm for explicitly
removing the redundancy from the genetic programs and
simplifying these programs online during the
evolutionary process. The new GP system with the
simplification is examined and compared with a standard
GP system on two regression and three classification
problems of varying difficulties. The results show that
the GP system employing a simplification component can
achieve superior efficiency with comparable or slightly
superior effectiveness to the standard GP system on
these problems. The programs evolved by the new GP
approach with the explicit simplification contain
``hidden patterns'' for a particular problem and are
relatively simple and easy to interpret.",