We show that given a k-bounded pseudo-boolean function f, one can always compute the cth moment off over regions of arbitrary radius in Hamming space in polynomial time using algebraic information from the adjacency s...
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We show that given a k-bounded pseudo-boolean function f, one can always compute the cth moment off over regions of arbitrary radius in Hamming space in polynomial time using algebraic information from the adjacency structure (where k and c are constants). This result has implications for evolutionary algorithms and local search algorithms because information about promising regions of the search space can be efficiently retrieved, even if the cardinality of the region is exponential in the problem size. Finally, we use our results to introduce a method of efficiently calculating the expected fitness of mutations for evolutionary algorithms. (C) 2011 Elsevier B.V. All rights reserved.
We consider classes of real-valued functions of boolean variables defined by disjunctive analogues of the submodular and supermodular functional inequalities, obtained by replacing in these inequalities addition by di...
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We consider classes of real-valued functions of boolean variables defined by disjunctive analogues of the submodular and supermodular functional inequalities, obtained by replacing in these inequalities addition by disjunction (max operator). The disjunctive analogues of submodular and supermodular functions are completely characterized by the syntax of their disjunctive normal forms. Classes of functions possessing combinations of these properties are also examined. A disjunctive representation theory based on one of these combination classes exhibits syntactic and algorithmic analogies with classical DNF theory. (C) 2003 Published by Elsevier B.V.
Classes of set functions defined by the positivity or negativity of the higher-order derivatives of their pseudo-boolean polynomial representations generalize those of monotone, supermodular, and submodular functions....
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Classes of set functions defined by the positivity or negativity of the higher-order derivatives of their pseudo-boolean polynomial representations generalize those of monotone, supermodular, and submodular functions. In this paper, these classes are characterized by functional inequalities and are shown to be closed both under algebraic closure conditions and a local closure criterion. It is shown that for every m : 1, in addition to the class of all set functions, there are only three other classes satisfying these algebraic and local closure conditions: those having positive, respectively negative, mth-order derivatives, and those having a polynomial representation of degree less than m.
In this paper we pursue the study of pseudo -booleanfunctions as ranking generators. The objective of the work is to find new insights between the relation of the degree m of a pseudo -boolean function and the rankin...
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In this paper we pursue the study of pseudo -booleanfunctions as ranking generators. The objective of the work is to find new insights between the relation of the degree m of a pseudo -boolean function and the rankings that can be generated by these insights. Based on a characterization theorem for pseudo -booleanfunctions of degree m, several observations are made. First, we verify that pseudo -booleanfunctions of degree m < n, where n is the search space dimension, cannot generate all the possible rankings of the solutions. Secondly, the sufficient condition for a ranking to be generated by a pseudo -boolean function of dimension ( n - 1) is presented, and also the necessary condition is conjectured. Finally, we observe that the same argument is not sufficient to prove which ranking can be generated by pseudo -booleanfunctions of degree m < n - 1 .
We examine classes of real-valued functions of 0-1 variables closed under algebraic operations as well as topological convergence, and having a certain local characteristic (requiring that any function not in the clas...
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We examine classes of real-valued functions of 0-1 variables closed under algebraic operations as well as topological convergence, and having a certain local characteristic (requiring that any function not in the class should have a k-variable minor not belonging to this class). It is shown that for k = 2, the only 4 maximal classes with these properties are those of submodular, supermodular, monotone increasing and monotone decreasing functions. All the 13 locally defined closed classes are determined and shown to be intersections of the 4 maximal ones. All maximal classes for k >= 3 are determined and characterized by the sign of higher order derivatives of the functions in the class. (C) 2009 Published by Elsevier B.V.
The problem of minimizing a pseudo-boolean function, that is, a real-valued function of 0-1 variables, arises in many applications. A quadratization is a reformulation of this nonlinear problem into a quadratic one, o...
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The problem of minimizing a pseudo-boolean function, that is, a real-valued function of 0-1 variables, arises in many applications. A quadratization is a reformulation of this nonlinear problem into a quadratic one, obtained by introducing a set of auxiliary binary variables. A desirable property for a quadratization is to introduce a small number of auxiliary variables. We present upper and lower bounds on the number of auxiliary variables required to define a quadratization for several classes of specially structured functions, such as functions with many zeros, symmetric, exact k-out-of-n, at least k-out-of-n and parity functions, and monomials with a positive coefficient, also called positive monomials. Most of these bounds are logarithmic in the number of original variables, and we prove that they are best possible for several of the classes under consideration. For positive monomials and for some other symmetric functions, a logarithmic bound represents a significant improvement with respect to the best bounds previously published, which are linear in the number of original variables. Moreover, the case of positive monomials is particularly interesting: indeed, when a pseudo-boolean function is represented by its unique multilinear polynomial expression, a quadratization can be obtained by separately quadratizing its monomials.
The power of players in a collective decision process is a central issue in game theory. For this reason. the concept of influence of players on a simple game has been introduced. More generally, the influence of vari...
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The power of players in a collective decision process is a central issue in game theory. For this reason. the concept of influence of players on a simple game has been introduced. More generally, the influence of variables on booleanfunctions has been defined and studied. We extend this concept to pseudo-boolean functions, thus making it possible to appraise the degree of influence of any coalition of players in cooperative games. In the case of monotone games, we also point out the links with the concept of interaction among players. Although they do not have the same meaning at all, both influence and interaction functions coincide on singletons with the so-called Banzhaf power index. We also define the influence of variables on continuous extensions of pseudo-boolean functions. In particular, the Lovasz extension, also called discrete Choquet integral, is used in multicriteria decision making problems as an aggregation operator. In such problems, the degree of influence of decision criteria on the aggregation process can then be quite relevant information. We give the explicit form of this influence for the Choquet integral and its classical particular cases. (C) 2000 Elsevier Science B.V. All rights reserved.
In this paper we present a class of valid inequalities as well as a class of facets for the cut-polytope of the complete graph. It is shown that many of the known classes of valid inequalities, e.g., triangle, hyperme...
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In this paper we present a class of valid inequalities as well as a class of facets for the cut-polytope of the complete graph. It is shown that many of the known classes of valid inequalities, e.g., triangle, hypermetric and cycle inequalities, belong to this class. By specializing some of the parameters, large classes of facets can be defined. It is shown that each of these classes contains at least (n/3)n/3 facets, where n greater-than-or-equal-to 10 denotes the number of vertices, and that the corresponding separation problems are polynomially solvable. These results are based on a one-to-one correspondence established between the set of valid inequalities (facets) for the cut-polytope of K(n+1), and the set of nonnegative (extremal) quadratic pseudo-boolean functions in n variables.
This paper studies the approximation of pseudo-boolean functions by linear functions and more generally by functions of (at most) a specified degree. Here a pseudo-boolean function means a real valued function defined...
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There exist general transforms that convert pseudo-boolean functions into k-bounded pseudo-boolean functions, for all k >= 2. In addition to these general transforms, there can also exist specialized transforms tha...
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ISBN:
(纸本)9781450371285
There exist general transforms that convert pseudo-boolean functions into k-bounded pseudo-boolean functions, for all k >= 2. In addition to these general transforms, there can also exist specialized transforms that can be applied in special cases. New results are presented examining what happens to the "bit flip" neighborhood when transforms are applied. Transforms condense variables in a particular order. We show that different variable orderings produce different results in terms of problem difficulty. We also prove new results about the embedding of the original function in the new k-bounded function. Finally, this paper also looks at how parameter optimization problems can be expressed as high precision k-bounded pseudo-boolean functions. This paper lays a foundation for the wider application of evolutionary algorithms to k-bounded pseudo-boolean functions.
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