An examination on the modularity of grammars in grammatical evolutionary design

This work furthers the understanding of modularity in grammar-based genetic programming approaches by analyzing how different grammars may be capable of producing the same phenotypes, but still display differences in performance on the same problems. This is done by creating four grammars with varying levels of modularity and using them with grammatical evolution to evolve floor plan designs. The results of this experimentation show how increases in modularity, brought about by simple modifications in the grammars, and increases in the quality of solutions go hand in hand. It also demonstrates how more modular grammars explore more individuals even while fitness remains the same or changes in only minor increments.