98 research outputs found
A standing ovation for Nigel: An informal study
No full textThis article analyses a series of emails thanking Nigel for his stewardship of JASSS and the characteristics of their authors. It identifies a correlation between two measures of author activity in social simulation research, but no pattern between these activity measures and the email timing. Instead, the sequence suggests a classic standing ovation effect.</p
The Extortion Relationship: A Computational Analysis
No full textSystematic extortion involves a long term parasitic relationship between the criminal and the victim. Game theory analysis has provided insight into the choices of individual hypothetical criminal and victim pairs. In this paper we present an agent-based model so as to extend the analysis to the relationship between extorters and other potential victims. The model is developed in two stages, the first to be closest to game theory, the second one making the decision informed by the social environment of the victim. The agent-based model shows the importance of social aspects for the functioning of extortion rackets
Cognitive variability
No full textThroughout psychological literature there are many, and ever increasing, references to a variable, usually presumed to be related to certain personality phenomena, which has~ been described as flexibility, fluidity, rigidity, perseveration, variability, and other similar terms. Generally, all these terms have refenced to the idea that the behaviour of people in different situations or of different people in the same situation··, varies along a continuum marked at one end by extreme limitation of reaction and at the other by extreme freedom of response. The use of this vague terminology and the fact that general concepts and definitions have been left far from clear, has rendered any approach to the topic extremely difficult, and I can echo with feeling the words of Chown (1959) when she said 11FeVJ major topics in contemporary psychology offer more promise than this one or present such a quagmire of confusion to the unwary investigator"! Probably the most satisfactory means of gaining a clear VieVJ of the field is with an historical perspective; I propose therefore to adopt this approach and to deal with the relevant literature under the general heading of - "Theories and types of rigidity fle:xibility11 It will be seen that it has been considered best to make a three-fold division of the literature - namely into that concerned with (l) 11Perseveration11 and "rigidity", (2) the rigid personality, and (3) Variability as such, although of necessity a certain amount of overlap doe
A compendium of modelling techniques
No full textThis Integration Insight provides a brief overview of the most popular modelling techniques used to analyse complex real-world problems, as well as some less popular but highly relevant techniques. The modelling methods are divided into three categories, with each encompassing a number of methods, as follows: 1) Qualitative Aggregate Models (Soft Systems Methodology, Concept Maps and Mind Mapping, Scenario Planning, Causal (Loop) Diagrams), 2) Quantitative Aggregate Models (Function fitting and Regression, Bayesian Nets, System of differential equations / Dynamical systems, System Dynamics, Evolutionary Algorithms) and 3) Individual Oriented Models (Cellular Automata, Microsimulation, Agent Based Models, Discrete Event Simulation, Social NetworkAnalysis). Each technique is broadly described with example uses, key attributes and reference material
A compendium of modelling techniques
No full textThis Integration Insight provides a brief overview of the most popular modelling techniques used to analyse complex real-world problems, as well as some less popular but highly relevant techniques. The modelling methods are divided into three categories, with each encompassing a number of methods, as follows: 1) Qualitative Aggregate Models (Soft Systems Methodology, Concept Maps and Mind Mapping, Scenario Planning, Causal (Loop) Diagrams), 2) Quantitative Aggregate Models (Function fitting and Regression, Bayesian Nets, System of differential equations / Dynamical systems, System Dynamics, Evolutionary Algorithms) and 3) Individual Oriented Models (Cellular Automata, Microsimulation, Agent Based Models, Discrete Event Simulation, Social NetworkAnalysis). Each technique is broadly described with example uses, key attributes and reference material
Functionality, Accuracy, and Feasibility: Talking with Modelers
No full textModels are an important part of many policy development processes, but meeting policy objectives relies on policy analysts engaging effectively with the modeling process and modelers understanding the policy issues. Furthermore, there are many different modeling methods, each with characteristics that potentially make it more or less suitable for analyzing a particular policy issue.This paper presents a novel framework to assist policy analysts to engage with modelers so as to make the best use of models. The framework has three dimensions: Functionality, Accuracy and Feasibility. Functionality concerns ways in which modeling can be used to support broader policy objectives, such as promoting negotiation or comparing options. Accuracy concerns how to best represent the fundamental features of the system being modeled, and relies on selecting an appropriate technique. Feasibility concerns practical issues such as access to data and modeling skills
A Spatial Approach to Network Generation for Three Properties: Degree Distribution, Clustering Coefficient and Degree Assortativity
No full textSocial networks generally display a positively skewed degree distribution and higher values for clustering coefficient and degree assortativity than would be expected from the degree sequence. For some types of simulation studies, these properties need to be varied in the artificial networks over which simulations are to be conducted. Various algorithms to generate networks have been described in the literature but their ability to control all three of these network properties is limited. We introduce a spatially constructed algorithm that generates networks with constrained but arbitrary degree distribution, clustering coefficient and assortativity. Both a general approach and specific implementation are presented. The specific implementation is validated and used to generate networks with a constrained but broad range of property values.Social Networks, Network Generation, Clustering Coefficient, Assortativity
Personal protective behaviour during an epidemic
No full textThe TELL ME simulation model is being developed to assist health authorities to understand the effects of their choices about how to communicate with citizens about protecting themselves from influenza epidemics. It will include an agent based model to simulate personal decisions to seek vaccination or adopt behaviour such as improved hand hygiene. This paper focusses on the design of the agents' decisions, using a combination of personal attitude, average local attitude, the local number of influenza cases and the case fatality rate. It also describes how personal decision making is connected to other parts of the model
A spatial approach to network generation for three properties:Degree distribution, clustering coefficient and degree assortativity
No full textSocial networks generally display a positively skewed degree distribution and higher values for clustering coefficient and degree assortativity than would be expected from the degree sequence. For some types of simulation studies, these properties need to be varied in the artificial networks over which simulations are to be conducted. Various algorithms to generate networks have been described in the literature but their ability to control all three of these network properties is limited. We introduce a spatially constructed algorithm that generates networks with constrained but arbitrary degree distribution, clustering coefficient and assortativity. Both a general approach and specific implementation are presented. The specific implementation is validated and used to generate networks with a constrained but broad range of property values.</p
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