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On Evolution, Search, Optimization, Genetic Algorithms and Martial Arts  Towards Memetic Algorithms
, 1989
"... Short abstract, isn't it? P.A.C.S. numbers 05.20, 02.50, 87.10 1 Introduction Large Numbers "...the optimal tour displayed (see Figure 6) is the possible unique tour having one arc fixed from among 10 655 tours that are possible among 318 points and have one arc fixed. Assuming that one could ..."
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Cited by 185 (10 self)
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Short abstract, isn't it? P.A.C.S. numbers 05.20, 02.50, 87.10 1 Introduction Large Numbers "...the optimal tour displayed (see Figure 6) is the possible unique tour having one arc fixed from among 10 655 tours that are possible among 318 points and have one arc fixed. Assuming that one could possibly enumerate 10 9 tours per second on a computer it would thus take roughly 10 639 years of computing to establish the optimality of this tour by exhaustive enumeration." This quote shows the real difficulty of a combinatorial optimization problem. The huge number of configurations is the primary difficulty when dealing with one of these problems. The quote belongs to M.W Padberg and M. Grotschel, Chap. 9., "Polyhedral computations", from the book The Traveling Salesman Problem: A Guided tour of Combinatorial Optimization [124]. It is interesting to compare the number of configurations of realworld problems in combinatorial optimization with those large numbers arising in Cosmol...
Species Adaption Genetic Algorithms: A Basis for a Continuing SAGA
, 1992
"... For Artificial Life applications it is useful to extend Genetic Algorithms from a finite search space with fixedlength genotypes to openended evolution with variablelength genotypes. A new theoretical analysis is required, as Holland's Schema Theorem only applies to fixed lengths. It will be argu ..."
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Cited by 106 (27 self)
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For Artificial Life applications it is useful to extend Genetic Algorithms from a finite search space with fixedlength genotypes to openended evolution with variablelength genotypes. A new theoretical analysis is required, as Holland's Schema Theorem only applies to fixed lengths. It will be argued, using concepts of epistasis and fitness landscapes drawn from theoretical biology, that in the long run a population must havegenotypes of nearly equal length, and this length can only increase slowly. As the length increases, the population will be nearly converged, and hence evolving as a species.
Evaluating Evolutionary Algorithms
 Artificial Intelligence
, 1996
"... Test functions are commonly used to evaluate the effectiveness of different search algorithms. However, the results of evaluation are as dependent on the test problems as they are on the algorithms that are the subject of comparison. Unfortunately, developing a test suite for evaluating competing se ..."
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Cited by 86 (14 self)
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Test functions are commonly used to evaluate the effectiveness of different search algorithms. However, the results of evaluation are as dependent on the test problems as they are on the algorithms that are the subject of comparison. Unfortunately, developing a test suite for evaluating competing search algorithms is difficult without clearly defined evaluation goals. In this paper we discuss some basic principles that can be used to develop test suites and we examine the role of test suites as they have been used to evaluate evolutionary search algorithms. Current test suites include functions that are easily solved by simple search methods such as greedy hillclimbers. Some test functions also have undesirable characteristics that are exaggerated as the dimensionality of the search space is increased. New methods are examined for constructing functions with different degrees of nonlinearity, where the interactions and the cost of evaluation scale with respect to the dimensionality of...
A Measure of Landscapes
 Evolutionary Computation
, 1995
"... The structure of a fitness landscape is still an illdefined concept. This paper introduces a statistical fitness landscape analysis, that can be used on a multitude of fitness landscapes. The result of this analysis is a statistical model that, together with some statistics denoting the explanatory ..."
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Cited by 55 (3 self)
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The structure of a fitness landscape is still an illdefined concept. This paper introduces a statistical fitness landscape analysis, that can be used on a multitude of fitness landscapes. The result of this analysis is a statistical model that, together with some statistics denoting the explanatory and predictive value of this model, can serve as a measure for the structure of the landscape. The analysis is based on a statistical time series analysis known as the BoxJenkins approach, that, among others, estimates the autocorrelations of a time series of fitness values generated by a random walk on the landscape. From these estimates, a correlation length for the landscape can be derived. Keywords: Fitness landscapes, Correlation structure, Correlation length 1 Introduction "We need a real theory relating the structure of rugged multipeaked fitness landscapes to the flow of a population upon those landscapes. We do not yet have such a theory." This quote, from Stuart A. Kauffman [...
Building Better Test Functions
 Proceedings of the Sixth International Conference on Genetic Algorithms
, 1995
"... We introduce basic guidelines for developing test suites for evolutionary algorithms and examine common test functions in terms of these guidelines. Two methods of designing test functions are introduced which address specific issues relevant to comparative studies of evolutionary algorithms. ..."
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Cited by 53 (5 self)
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We introduce basic guidelines for developing test suites for evolutionary algorithms and examine common test functions in terms of these guidelines. Two methods of designing test functions are introduced which address specific issues relevant to comparative studies of evolutionary algorithms. The first method produces representation invariant functions.
Evolving Better Representations through Selective Genome Growth
 In Proceedings of the IEEE World Congress on Computational Intelligence
, 1994
"... The choice of how to represent the search space for a genetic algorithm (GA) is critical to the GA's performance. Representations are usually engineered by hand and fixed for the duration of the GA run. Here a new method is described in which the degrees of freedom of the representation  i.e. the ..."
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Cited by 44 (4 self)
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The choice of how to represent the search space for a genetic algorithm (GA) is critical to the GA's performance. Representations are usually engineered by hand and fixed for the duration of the GA run. Here a new method is described in which the degrees of freedom of the representation  i.e. the genes  are increased incrementally. The phenotypic effects of the new genes are randomly drawn from a space of different functional effects. Only those genes that initially increase fitness are kept. The genotypephenotype map that results from this selection during the construction of the genome allows better adaptation. This effect is illustrated with the NK landscape model. The resulting genotypephenotype maps are much less epistatic than unselected maps would be, having extremely low values of "K"  the number of fitness components affected by each gene. Moreover, these maps are exquisitely tuned to the specifics of the epistatic fitness function, creating adaptive landscapes that ...
Circle In The Round: State Space Attractors for Evolved Sighted Robots
"... This paper presents an analysis of an artificially evolved dynamical networkbased control system for a simulated autonomous mobile robot engaged in simple visually guided tasks. ..."
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Cited by 39 (9 self)
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This paper presents an analysis of an artificially evolved dynamical networkbased control system for a simulated autonomous mobile robot engaged in simple visually guided tasks.
The Advantages of Landscape Neutrality in Digital Circuit Evolution
, 2000
"... . The paper studies the role of neutrality in the fitness landscapes associated with the evolutionary design of digital circuits and particularly the threebit binary multiplier. For the purpose of the study, digital circuits are evolved extrinsically on an array of logic cells. To evolve on an ..."
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Cited by 37 (15 self)
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. The paper studies the role of neutrality in the fitness landscapes associated with the evolutionary design of digital circuits and particularly the threebit binary multiplier. For the purpose of the study, digital circuits are evolved extrinsically on an array of logic cells. To evolve on an array of cells, a genotypephenotype mapping has been devised by which neutrality can be embedded in the resulting fitness landscape. It is argued that landscape neutrality is beneficial for digital circuit evolution. 1 Introduction Digital circuit evolution is a process of evolving configurations of logic gates for some prespecified computational program. Often the aim is for a highly efficient electronic circuit to emerge in a population of instances of the program. Digital electronic circuits have been evolved intrinsically [1] and extrinsically [26]. The former is associated with an evolutionary process in which each evolved electronic circuit is built and tested on hardware, whil...