 
Summary: Advances in Ordered Greed
Peter G. Anderson1
and Daniel Ashlock
Laboratory for Applied Computing, RIT, Rochester, NY
and Iowa State University, Ames IA
Abstract
Ordered Greed is a form of genetic algorithm that uses
a population of permutations whose fitnesses depend on
their use as the orders in which parts of a problem are
solved. For example, a permutation may specify the or
der of the rows in which chessboard queens are placed to
try to avoid attacks by other queens, or it may specify the
order in which vertices of a graph are colored to avoid ad
jacent vertices getting the same color. The problems men
tioned are surrogates for practical, difficult, reallife prob
lems such as scheduling.
Ordered greed requires its own form of crossover. We
have developed and investigate two new crossover opera
tors. The first uses the standard combinatorial mathematics
notion of permutations' signatures, which are a list of num
