News from the Centre for Policy Modelling, including announcements of: new papers, special issues, books, workshops, projects, jobs and study opportunities.

21 November, 2008

CPM Report 08-199: Bootstrapping Knowledge about Social Phenomena using Simulation Models - Bruce Edmonds

Formidable difficulties face anyone trying to model social phenomena using a formal system, such as a computer program. The differences between formal systems and complex, multi-facetted and meaning-laden social systems are so fundamental that many will criticise any attempt to bridge this gap. Despite this, there are those who are so bullish about the project of social simulation that they appear to believe that simple computer models, that are also useful and reliable indicators of how aspects of society works, are not only possible but within our grasp. This paper seeks to pour water on such optimism but, on the other hand, show that useful computational models might be ‘evolved’. In this way it is disagreeing with both naive positivist and relativistic post-modernist positions. However this will require a greater ‘selective pressure’ against models that are not grounded in evidence, ‘floating models’, and will result in a plethora of complex and context-specific models.

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CPM Report 08-198: System Farming - Bruce Edmonds

We discuss the implications of emergence and complexity for the management of complex distributed systems (CDS). We argue that while formal design methods may play a role, they have distinct limitations where it comes to complex systems. There are similar limitations to statistical methods. Thus we must look to other ways of managing these systems, involving a shift from: prior one-off design towards post hoc continual management; from predictive abstract theory towards detailed descriptive modelling to guide monitoring and aid diagnosis; from system optimisation to simple disaster prevention; from single models to many models; from single well-designed mechanisms to multiple overlapping mechanisms; from individual to collective effort. We call upon those in the SASO community to explicitly reject those tenets that are only useful with simple systems. In other words, when trying to understand CDS, become more like zoologists rather than mathematicians and when managing them becoming more like farmers than engineers (at least in the classic sense).

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CPM Report 08-197: Emotions in social interactions: unfolding emotional experience - Claudia Marinetti, Penny Moore, Pablo Lucas dos Anjos and Brian P

In the unremitting complexity of social life, emotions play a key role in defining and regulating our
relationships with others and, more generally, with the environment surrounding us. Our emotional reactions to other people influence how those others react to us, and to a certain extent how future encounters will develop. At the same time, our own emotional behaviour is shaped by others’ thoughts and deeds. Although emotions undeniably have personal and subjective aspects, they are usually experienced in a social context and acquire their significance in relation to this context (see also the “Socially situated affective systems” chapter, WP7, in this handbook).

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CPM Report 08-196: "Death to . . . !": On Opinion Dynamics in Conict-Torn Afghanistan - Armando Geller and Nanda Wijermans

Crowds and riots in contemporary conflict are only little understood. However, it is fairly well understood that the emergence of crowds and riots in conflict regions has a severe and lasting impact on the security situation. On the basis of an existing and cross-validated model of Afghan power structures we demonstrate what role opinion dynamics play in the evolution of a critical social condition preceding the emergence of crowds and riots. It is explained how information on security incidences spreads within an artificial society and when such a turning point is reached. The influence of network structures on the spread of information and the role opinion leaders play is explored. We find that small world network structures lead to dynamics that are volatile, unpredictable and performative in nature. It is also shown that opinion leaders have a catalytic effect on the information distribution processes. These findings bear importance for policy makers and practitioners in the field.

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CPM Report 08-195: Policy Modelling: Problems and Prospects - Scott Moss

Policy modelling is the application of agent based social simulation to the analysis of social policies. While agent based modelling has been seen as a promising technique for policy analysis in a number of applications such as water demand and land use management, it has not become an important tool of business and public policy analysis more widely. The purpose of this paper is systematically to set policy modelling in a wider scientific context than has been attempted previously and to use that context to explore the general conditions in which policy modelling is appropriate and the problems to be faced in convincing working policy analysts why and when it is the most appropriate tool of analysis available to them.

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