918 resultados para Elecció social -- Models matemàtics
Resumo:
A major challenge in studying social behaviour stems from the need to disentangle the behaviour of each individual from the resulting collective. One way to overcome this problem is to construct a model of the behaviour of an individual, and observe whether combining many such individuals leads to the predicted outcome. This can be achieved by using robots. In this review we discuss the strengths and weaknesses of such an approach for studies of social behaviour. We find that robots-whether studied in groups of simulated or physical robots, or used to infiltrate and manipulate groups of living organisms-have important advantages over conventional individual-based models and have contributed greatly to the study of social behaviour. In particular, robots have increased our understanding of self-organization and the evolution of cooperative behaviour and communication. However, the resulting findings have not had the desired impact on the biological community. We suggest reasons for why this may be the case, and how the benefits of using robots can be maximized in future research on social behaviour.
Resumo:
Abstract Sitting between your past and your future doesn't mean you are in the present. Dakota Skye Complex systems science is an interdisciplinary field grouping under the same umbrella dynamical phenomena from social, natural or mathematical sciences. The emergence of a higher order organization or behavior, transcending that expected of the linear addition of the parts, is a key factor shared by all these systems. Most complex systems can be modeled as networks that represent the interactions amongst the system's components. In addition to the actual nature of the part's interactions, the intrinsic topological structure of underlying network is believed to play a crucial role in the remarkable emergent behaviors exhibited by the systems. Moreover, the topology is also a key a factor to explain the extraordinary flexibility and resilience to perturbations when applied to transmission and diffusion phenomena. In this work, we study the effect of different network structures on the performance and on the fault tolerance of systems in two different contexts. In the first part, we study cellular automata, which are a simple paradigm for distributed computation. Cellular automata are made of basic Boolean computational units, the cells; relying on simple rules and information from- the surrounding cells to perform a global task. The limited visibility of the cells can be modeled as a network, where interactions amongst cells are governed by an underlying structure, usually a regular one. In order to increase the performance of cellular automata, we chose to change its topology. We applied computational principles inspired by Darwinian evolution, called evolutionary algorithms, to alter the system's topological structure starting from either a regular or a random one. The outcome is remarkable, as the resulting topologies find themselves sharing properties of both regular and random network, and display similitudes Watts-Strogtz's small-world network found in social systems. Moreover, the performance and tolerance to probabilistic faults of our small-world like cellular automata surpasses that of regular ones. In the second part, we use the context of biological genetic regulatory networks and, in particular, Kauffman's random Boolean networks model. In some ways, this model is close to cellular automata, although is not expected to perform any task. Instead, it simulates the time-evolution of genetic regulation within living organisms under strict conditions. The original model, though very attractive by it's simplicity, suffered from important shortcomings unveiled by the recent advances in genetics and biology. We propose to use these new discoveries to improve the original model. Firstly, we have used artificial topologies believed to be closer to that of gene regulatory networks. We have also studied actual biological organisms, and used parts of their genetic regulatory networks in our models. Secondly, we have addressed the improbable full synchronicity of the event taking place on. Boolean networks and proposed a more biologically plausible cascading scheme. Finally, we tackled the actual Boolean functions of the model, i.e. the specifics of how genes activate according to the activity of upstream genes, and presented a new update function that takes into account the actual promoting and repressing effects of one gene on another. Our improved models demonstrate the expected, biologically sound, behavior of previous GRN model, yet with superior resistance to perturbations. We believe they are one step closer to the biological reality.
Resumo:
El present treball de recerca és una primera aproximació teòrico-metodològica a l'estudi de “l’entrevista filmada” per a la recerca social. En ell s'analitza la tensió conceptual entre els dos termes: "l'entrevista" i el "filmar". Així mateix, es posen a prova els conceptes plantejats en diferents contextos i pràctiques de recerca, atenent específicament als models de col•laboració i els rols aquí sorgits, amb l'objectiu de formular un marc interpretatiu de les qüestions a les quals s'enfronta l'investigador a l'hora de planejar, filmar i usar l'entrevista en una recerca social
Resumo:
Since ethical concerns are calling for more attention within Operational Research, we present three approaches to combine Operational Research models with ethics. Our intention is to clarify the trade-offs faced by the OR community, in particular the tension between the scientific legitimacy of OR models (ethics outside OR models) and the integration of ethics within models (ethics within OR models). Presenting and discussing an approach that combines OR models with the process of OR (ethics beyond OR models), we suggest rigorous ways to express the relation between ethics and OR models. As our work is exploratory, we are trying to avoid a dogmatic attitude and call for further research. We argue that there are interesting avenues for research at the theoretical, methodological and applied levels and that the OR community can contribute to an innovative, constructive and responsible social dialogue about its ethics.
Resumo:
It has long been standard in agency theory to search for incentive-compatible mechanisms on the assumption that people care only about their own material wealth. However, this assumption is clearly refuted by numerous experiments, and we feel that it may be useful to consider nonpecuniary utility in mechanism design and contract theory. Accordingly, we devise an experiment to explore optimal contracts in an adverse-selection context. A principal proposes one of three contract menus, each of which offers a choice of two incentive-compatible contracts, to two agents whose types are unknown to the principal. The agents know the set of possible menus, and choose to either accept one of the two contracts offered in the proposed menu or to reject the menu altogether; a rejection by either agent leads to lower (and equal) reservation payoffs for all parties. While all three possible menus favor the principal, they do so to varying degrees. We observe numerous rejections of the more lopsided menus, and approach an equilibrium where one of the more equitable contract menus (which one depends on the reservation payoffs) is proposed and agents accept a contract, selecting actions according to their types. Behavior is largely consistent with all recent models of social preferences, strongly suggesting there is value in considering nonpecuniary utility in agency theory.
Resumo:
Objective: This research presents the construction of an attributional questionnaire concerning the different parental models and factors that are involved in family interactions. Method: A mixed methodology was used as a foundation to develop items and respective pilots that allowed checking the validity and internal consistency of the instrument using expert judgment. Results: An instrument of 36 statements was organized into 12 categories to explore the parental models according to the following factors: parental models, breeding patterns, attachment bonds and guidelines for success, and promoted inside family contexts. Analyzing these factors contributes to the children’s development within the familiar frown, and the opportunity for socio-educational intervention. Conclusion: It is assumed that the family context is as decisive as the school context; therefore, exploring the nature of parental models is required to understand the features and influences that contribute to the development of young people in any social context.
Resumo:
Developing a sense of identity is a crucial psychosocial task for young people. The purpose of this study was to evaluate identity development in French-speaking adolescents and emerging adults (in France and Switzerland) using a process-oriented model of identity formation including five dimensions (i.e., exploration in breadth, commitment making, exploration in depth, identification with commitment, and ruminative exploration). The study included participants from three different samples (total N = 2239, 66.7% women): two samples of emerging adult student and one sample of adolescents. Results confirmed the hypothesized five-factor dimensional model of identity in our three samples and provided evidence for convergent validity of the model. The results also indicated that exploration in depth might be subdivided in two aspects: a first form of exploration in depth leading to a better understanding and to an increase of the strength of current commitments and a second form of exploration in depth leading to a re-evaluation and a reconsideration of current commitments. Further, the identity status cluster solution that emerged is globally in line with previous literature (i.e., achievement, foreclosure, moratorium, carefree diffusion, diffused diffusion, undifferentiated). However, despite a structural similarity, we found variations in identity profiles because identity development is shaped by cultural context. These specific variations are discussed in light of social, educational and economic differences between France and the French-speaking part of Switzerland. Implications and suggestions for future research are offered.
Resumo:
We survey the population genetic basis of social evolution, using a logically consistent set of arguments to cover a wide range of biological scenarios. We start by reconsidering Hamilton's (Hamilton 1964 J. Theoret. Biol. 7, 1-16 (doi:10.1016/0022-5193(64)90038-4)) results for selection on a social trait under the assumptions of additive gene action, weak selection and constant environment and demography. This yields a prediction for the direction of allele frequency change in terms of phenotypic costs and benefits and genealogical concepts of relatedness, which holds for any frequency of the trait in the population, and provides the foundation for further developments and extensions. We then allow for any type of gene interaction within and between individuals, strong selection and fluctuating environments and demography, which may depend on the evolving trait itself. We reach three conclusions pertaining to selection on social behaviours under broad conditions. (i) Selection can be understood by focusing on a one-generation change in mean allele frequency, a computation which underpins the utility of reproductive value weights; (ii) in large populations under the assumptions of additive gene action and weak selection, this change is of constant sign for any allele frequency and is predicted by a phenotypic selection gradient; (iii) under the assumptions of trait substitution sequences, such phenotypic selection gradients suffice to characterize long-term multi-dimensional stochastic evolution, with almost no knowledge about the genetic details underlying the coevolving traits. Having such simple results about the effect of selection regardless of population structure and type of social interactions can help to delineate the common features of distinct biological processes. Finally, we clarify some persistent divergences within social evolution theory, with respect to exactness, synergies, maximization, dynamic sufficiency and the role of genetic arguments.
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Due to practical difficulties in obtaining direct genetic estimates of effective sizes, conservation biologists have to rely on so-called 'demographic models' which combine life-history and mating-system parameters with F-statistics in order to produce indirect estimates of effective sizes. However, for the same practical reasons that prevent direct genetic estimates, the accuracy of demographic models is difficult to evaluate. Here we use individual-based, genetically explicit computer simulations in order to investigate the accuracy of two such demographic models aimed at investigating the hierarchical structure of populations. We show that, by and large, these models provide good estimates under a wide range of mating systems and dispersal patterns. However, one of the models should be avoided whenever the focal species' breeding system approaches monogamy with no sex bias in dispersal or when a substructure within social groups is suspected because effective sizes may then be strongly overestimated. The timing during the life cycle at which F-statistics are evaluated is also of crucial importance and attention should be paid to it when designing field sampling since different demographic models assume different timings. Our study shows that individual-based, genetically explicit models provide a promising way of evaluating the accuracy of demographic models of effective size and delineate their field of applicability.
Resumo:
Since ethical concerns are calling for more attention within OperationalResearch, we present three approaches to combine Operational Researchmodels with ethics. Our intention is to clarify the trade-offs faced bythe OR community, in particular the tension between the scientificlegitimacy of OR models (ethics outside OR models) and the integrationof ethics within models (ethics within OR models). Presenting anddiscussing an approach that combines OR models with the process of OR(ethics beyond OR models), we suggest rigorous ways to express the relationbetween ethics and OR models. As our work is exploratory, we are trying toavoid a dogmatic attitude and call for further research. We argue thatthere are interesting avenues for research at the theoretical,methodological and applied levels and that the OR community can contributeto an innovative, constructive and responsible social dialogue about itsethics.
Resumo:
This paper shows that models where preferences of individuals dependnot only on their allocations, but also on the well-being of otherpersons, can produce both large and testable effects. We study theallocation of workers with heterogeneous productivities to firms. Weshow that even small deviations from purely selfish preferences leadsto widespread workplace skill segregation. That is, workers ofdifferent abilities tend to work in di¤erent firms, as long as theycare somewhat more about the utilities of workers who are close .
Resumo:
A gestão das Instituições de Ensino Superior está a ser repensada num contexto de globalização tendo em conta a missão destas, a responsabilidade e a sua cultura (ou culturas), impondo-se novos modelos de gestão e governação. A Qualidade e a Responsabilidade Social do Ensino Superior constituem um tema pertinente e actual. As transformações estruturais que as sociedades atravessam aconselham e justificam da parte do Ensino Superior uma atitude consentânea com as necessidades daquelas. Os desafios que, as Instituições de Ensino Superior enfrentam, exigem novas perspectivas estratégicas e nova visão perante cenários de incerteza que surgem a nível mundial, desempenhando a liderança um papel fundamental na qualidade destas instituições. Neste sentido, lança-se no presente estudo, a seguinte questão: Que Modelos de Gestão e Governação contribuem para a melhoria da Qualidade no Ensino Superior? A metodologia utilizada para a realização deste estudo passa pelo delineamento de uma estratégia com cinco fases: elaboração de um plano ajustável à evolução do trabalho, levantamento do estado da arte de uma forma gradual, trabalho de pesquisa e criação, escrita da tese e análise crítica e reflexão. Para além de outros aspectos relevantes no domínio do Ensino Superior, foram estudados diversos modelos, Modelos de Excelência, modelos para implementação de Sistemas de Gestão da Qualidade, Gestão Ambiental, Gestão da Segurança e Saúde do Trabalho, Gestão de Risco; entre outros. Criaram-se diversos Indicadores de Responsabilidade Social neste contexto e foi feito um estudo piloto no âmbito da Responsabilidade Social em Instituições de Ensino Superior. Por último, destacaram-se as conclusões que decorrem do estudo piloto efectuado, bem como reflexões que surgem da investigação teórica realizada. O estudo piloto efectuado permitiu concluir, por exemplo, que existem indícios de algum alheamento no seio das Instituições às temáticas relacionadas com os princípios éticos e com a educação ambiental. Por outro lado, uma grande parte dos indivíduos inquiridos disseram não ter qualquer opinião quando confrontados com questões sobre Participação Social Responsável, Investigação Socialmente Útil e Gestão Social do Conhecimento. Conclui-se que as questões para as pessoas ainda são muito vagas, daí que, faça sentido o debate de todas estas questões, bem como estudos que contribuam para uma mudança de paradigma relativamente à educação, e em particular no Ensino Superior, com vista à qualidade, num sentido abrangente.
Resumo:
The management of Higher Education Institutions is being rethought, with the mission and culture of the institutions changing due to globalization, resulting in new models of management and governance. The quality of Higher Education and its obligations to society are of current importance. The structural changes that the society has gone through requires a response in higher education that matches the changing needs of the society. Higher Education Institutions require new perspectives and a new strategic vision to cope with the uncertainty arising at a global scale, and this plays a role in their quality and whether they are leading institutions. Thus the following question arises: Which forms of management and governance contribute to the improvement of quality in higher education? The methodology for this study was designed with five stages: preparation of a plan of work within the thesis, the gradual progression to understanding the up-to-date understanding of Higher Education Research, generating research hypotheses and creating further understanding, writing the thesis with critical analysis and reflection. In addition to other relevant issues in higher education, different models were studied: Models of excellence, Models for implementation of Quality Management Systems, Environmental Management, Occupational Health and Safety Management, Risk Management, among others. Several indicators of Social Responsibility were created in this context and a pilot study was conducted in the area of Social Responsibility in Higher Education Institutions. Finally the conclusions resulting from the pilot study are presented and questions arising from the theoretical research are discussed. For example, the pilot study showed that there are indicators of a lack of understanding within the institutions to issues related to ethical and environmental education. Moreover, a large proportion of respondents said individuals have no opinion when confronted with questions on Responsible Social Involvement and Social Research and Social Management of Useful Knowledge. It is concluded that people have a vague awareness of these issues, so these concepts are new to them.
Resumo:
The management of Higher Education Institutions is being rethought, with the mission and culture of the institutions changing due to globalization, resulting in new models of management and governance. The quality of Higher Education and its obligations to society are of current importance. The structural changes that the society has gone through requires a response in higher education that matches the changing needs of the society. Higher Education Institutions require new perspectives and a new strategic vision to cope with the uncertainty arising at a global scale, and this plays a role in their quality and whether they are leading institutions. Thus the following question arises: Which forms of management and governance contribute to the improvement of quality in higher education? The methodology for this study was designed with five stages: preparation of a plan of work within the thesis, the gradual progression to understanding the up-to-date understanding of Higher Education Research, generating research hypotheses and creating further understanding, writing the thesis with critical analysis and reflection. In addition to other relevant issues in higher education, different models were studied: Models of excellence, Models for implementation of Quality Management Systems, Environmental Management, Occupational Health and Safety Management, Risk Management, among others. Several indicators of Social Responsibility were created in this context and a pilot study was conducted in the area of Social Responsibility in Higher Education Institutions. Finally the conclusions resulting from the pilot study are presented and questions arising from the theoretical research are discussed. For example, the pilot study showed that there are indicators of a lack of understanding within the institutions to issues related to ethical and environmental education. Moreover, a large proportion of respondents said individuals have no opinion when confronted with questions on Responsible Social Involvement and Social Research and Social Management of Useful Knowledge. It is concluded that people have a vague awareness of these issues, so these concepts are new to them.
Resumo:
The management of Higher Education Institutions is being rethought, with the mission and culture of the institutions changing due to globalization, resulting in new models of management and governance. The quality of Higher Education and its obligations to society are of current importance. The structural changes that the society has gone through requires a response in higher education that matches the changing needs of the society. Higher Education Institutions require new perspectives and a new strategic vision to cope with the uncertainty arising at a global scale, and this plays a role in their quality and whether they are leading institutions. Thus the following question arises: Which forms of management and governance contribute to the improvement of quality in higher education? The methodology for this study was designed with five stages: preparation of a plan of work within the thesis, the gradual progression to understanding the up-to-date understanding of Higher Education Research, generating research hypotheses and creating further understanding, writing the thesis with critical analysis and reflection. In addition to other relevant issues in higher education, different models were studied: Models of excellence, Models for implementation of Quality Management Systems, Environmental Management, Occupational Health and Safety Management, Risk Management, among others. Several indicators of Social Responsibility were created in this context and a pilot study was conducted in the area of Social Responsibility in Higher Education Institutions. Finally the conclusions resulting from the pilot study are presented and questions arising from the theoretical research are discussed. For example, the pilot study showed that there are indicators of a lack of understanding within the institutions to issues related to ethical and environmental education. Moreover, a large proportion of respondents said individuals have no opinion when confronted with questions on Responsible Social Involvement and Social Research and Social Management of Useful Knowledge. It is concluded that people have a vague awareness of these issues, so these concepts are new to them.