Optimization Aspects of Carcinogenesis

Any process in which competing solutions replicate with errors and numbers of their copies depend on their respective fitnesses is the evolutionary optimization process. As during carcinogenesis mutated genomes replicate according to their respective qualities, carcinogenesis obviously qualifies as the evolutionary optimization process and conforms to common mathematical basis. The optimization view accents statistical nature of carcinogenesis proposing that during it the crucial role is actually played by the allocation of trials. Optimal allocation of trials requires reliable schemas' fitnesses estimations which necessitate appropriate, fitness landscape dependent, statistics of population. In the spirit of the applied conceptual framework, features which are known to decrease efficiency of any evolutionary optimization procedure (or inhibit it completely) are anticipated as "therapies" and reviewed. Strict adherence to the evolutionary optimization framework leads us to some counterintuitive implications which are, however, in agreement with recent experimental findings, such as sometimes observed more aggressive and malignant growth of therapy surviving cancer cells

On the locality of Representations

Darstellungsschich

The role of Walsh structure and ordinal linkage in the optimisation of pseudo-Boolean functions under monotonicity invariance.

Optimisation heuristics rely on implicit or explicit assumptions about the structure of the black-box fitness function they optimise. A review of the literature shows that understanding of structure and linkage is helpful to the design and analysis of heuristics. The aim of this thesis is to investigate the role that problem structure plays in heuristic optimisation. Many heuristics use ordinal operators; which are those that are invariant under monotonic transformations of the fitness function. In this thesis we develop a classification of pseudo-Boolean functions based on rank-invariance. This approach classifies functions which are monotonic transformations of one another as equivalent, and so partitions an infinite set of functions into a finite set of classes. Reasoning about heuristics composed of ordinal operators is, by construction, invariant over these classes. We perform a complete analysis of 2-bit and 3-bit pseudo-Boolean functions. We use Walsh analysis to define concepts of necessary, unnecessary, and conditionally necessary interactions, and of Walsh families. This helps to make precise some existing ideas in the literature such as benign interactions. Many algorithms are invariant under the classes we define, which allows us to examine the difficulty of pseudo-Boolean functions in terms of function classes. We analyse a range of ordinal selection operators for an EDA. Using a concept of directed ordinal linkage, we define precedence networks and precedence profiles to represent key algorithmic steps and their interdependency in terms of problem structure. The precedence profiles provide a measure of problem difficulty. This corresponds to problem difficulty and algorithmic steps for optimisation. This work develops insight into the relationship between function structure and problem difficulty for optimisation, which may be used to direct the development of novel algorithms. Concepts of structure are also used to construct easy and hard problems for a hill-climber

What makes a problem hard for a genetic algorithm? Some anomalous results and their explanation

What makes a problem easy or hard for a genetic algorithm (GA)? This question has become increasingly important as people have tried to apply the GA to ever more diverse types of problems. Much previous work on this question has studied the relationship between GA performance and the structure of a given fitness function when it is expressed as a Walsh polynomial . The work of Bethke, Goldberg, and others has produced certain theoretical results about this relationship. In this article we review these theoretical results, and then discuss a number of seemingly anomalous experimental results reported by Tanese concerning the performance of the GA on a subclass of Walsh polynomials, some members of which were expected to be easy for the GA to optimize. Tanese found that the GA was poor at optimizing all functions in this subclass, that a partitioning of a single large population into a number of smaller independent populations seemed to improve performance, and that hillelimbing outperformed both the original and partitioned forms of the GA on these functions. These results seemed to contradict several commonly held expectations about GAs.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46892/1/10994_2004_Article_BF00993046.pd

Covers

This paper introduces the theory of covers for functions defined over binary variables. Covers formalize the notion of decomposability. Large complex problems are decomposed into subproblems each containing fewer variables, which can then be solved in parallel. Practical applications of the benefits from decomposition include the parallel architecture of supercomputers, the divisionalization of firms, and the decentralization of economic activity. In this introductory paper, we show how covers also shed light on the choice among public projects with complementarities. Further, covers provide a measure of complexity/decomposability with respect to contour sets, allowing for nonlinear effects which occur near the optimum to receive more weight than nonlinear effects arbitrarily located in the domain. Finally, as we demonstrate, covers can be used to analyze and to calibrate search algorithms

Beyond the eye of the beholder : perceived gender role departure in close relationships

The purpose of this study was to investigate the phenomenon of perceived gender role departure (PGRD) as it relates to both perceived stigma and individuals’ perceptions of their romantic relationships. To accomplish this task, first a novel method for measuring PGRD and its four sub-dimensions (source, type, magnitude, and direction) was advanced and tested for viability among a sample of United States adults (N = 401). Results indicated that the scale was viable. Following this the associations between and among each of the sub-dimensions of PGRD and perceived stigma were investigated. Results indicated that the interaction of source and magnitude was most strongly related to perceived stigma. Then, associations between perceived stigma and individuals’ perceptions of their romantic relationships were proposed and tested. Perceived stigma was significantly and negatively associated with investment model variables (commitment, investment, satisfaction, perceived quality of alternatives) and intimacy, and significantly positively associated with relational uncertainty. Finally, a meditational model was proposed, wherein perceived stigma acted to intervene in the relationship between PGRD and individuals’ perceptions of their romantic relationship. Perceived stigma was found to significantly mediate the negative association between PGRD and investment model variables, and to significantly mediate the positive association between vi PGRD and relational uncertainty. The results of this study are discussed in terms of their potential contributions to biosocial construction theory and also to discourses that resist binary notions of gender. Finally, the potential applicability of the results to designing interventions for individuals or couples who feel that their relationships might be negatively impacted by PGRD are offered.Communication Studie

Materialism and happiness as predictors of willingness to buy counterfeit luxury brands

The study examines the effect of material values – namely material success, material happiness, material essentiality and material distinctiveness – and life satisfaction and lawfulness with regards to consumers’ attitude toward counterfeit luxury brands and their affect on consumers’ willingness to buy counterfeit luxury brands. To test the research model, a new scale to measure and conceptualize materialism was developed and two new constructs: “material essentiality” and “material distinctiveness” were created