The Delta Coding, developed by Mathias and Whitely?, is not based on modifying the actual number of bits used to represent a function parameter, but rather, it alters the mapping of the genere to its phenotypic value. It changes the representation of search space dynamically in every iteration and re-initialize the population in every δ step. By this means, Delta coding preserves the diversity of the population in order to avoid premature convergence. However, Delta coding needs the Hamming distance among individuals as the adaptive search guide, which cannot solve the conflict between reliability and efficiency. In other words, this step may cause the efficiency decrease of the genetic algorithm.
(From RefLeung2002)
Why would you do this? Need to look at original source --Robin