Search on spin glass-like landscapes

The limited space for this review precludes a proper review of the extensive literature on this subject. I will confine this section to results concerning setting selection stringency and mutation rate, as these issues are critical to any laboratory implementation of search. There are four relevant bodies of literature adaptive walk studies, theoretical immune system studies, formal spin glass studies, and theoretical genetic algorithm studies. Much of the adaptive walk literature has already been discussed above. 

The theory to calculate these relationships, particularly in the context of applied molecular evolution, is still sparse. The remainder of this section highlights some potentially very useful concepts and approaches for experiment protocol design. The summary of literature here is by no means complete. 

Another approach is possible if the affinity landscape correlation is known. The mutation rate in a given round can be based on the average fitness of the library in that round. The optimal mutation distance (see above) for a correlated landscape depends on the fitness of the point being mutated and can be converted into a mutation rate. More generally, if there is an estimate of the distribution of fitnesses around a population s average fitness as a function of number of rounds, theoretically a distribution of optimal mutation distances could be calculated, which could yield a mutation rate schedule for an evolving population. 

Genetic algorithm approaches Genetic algorithms (GAs) are a computer search technique very similar in approach to laboratory selection/amplification methods such as 

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