A Building Block Favoring Reordering Method for Gene Positions in
 		 Genetic Algorithms

Onur Tolga Sehitoglu             Göktürk Üçoluk                            
Dept. of Computer Engineering    Dept. of Computer Engineering                       
METU, Ankara                     METU, Ankara
onur@ceng.metu.edu.tr            ucoluk@ceng.metu.edu.tr                     
 
This work proposes an algorithm to speed-up convergence of genetic
algorithms that is based on the investigation of neighbouring gene
values of the successful individuals of the chromosome pool. By
performing some statistical inference on neighbour gene values,
coherent behaving genes are detected. It is claimed that those coherent
acting genes are belonging to the  same building block that leads to
the solution. It is desirable to keep genes of the same building block
together to let them --probabilistically-- live together in next
generations.  Therefore, a reordering of the gene positions is
performed, periodically. The proposed algorithm is implemented for a
minimum area non-overlapping rectangle placement problem and results
are compared to a classical GA implementation.