Crowd modeling and simulation technologies

As a collective and highly dynamic social group, the human crowd is a fascinating phenomenon that has been frequently studied by experts from various areas. Recently, computer-based modeling and simulation technologies have emerged to support investigation of the dynamics of crowds, such as a crowd's behaviors under normal and emergent situations. This article assesses the major existing technologies for crowd modeling and simulation. We first propose a two-dimensional categorization mechanism to classify existing work depending on the size of crowds and the time-scale of the crowd phenomena of interest. Four evaluation criteria have also been introduced to evaluate existing crowd simulation systems from the point of view of both a modeler and an end-user. We have discussed some influential existing work in crowd modeling and simulation regarding their major features, performance as well as the technologies used in this work. We have also discussed some open problems in the area. This article will provide the researchers with useful information and insights on the state of the art of the technologies in crowd modeling and simulation as well as future research directions.</jats:p

Die Rolle der Ökonomik in der Wissenschaftsphilosophie: Eine kritische Würdigung aus Sicht der Economics of Scientific Knowledge und eine Agentenbasierte Modellierung zur Konsensbildung mit eingeschränkt rationalen, adaptiv handelnden heterogenen Akteuren

Die Dissertation wendet sich insbesondere der Rolle der Ökonomik auf der Metaebene der wissenschaftsphilosophischen Argumentation zu. Ziel ist zu klären, welchen Erklärungsgehalt ökonomische Instrumente in der Wissenschaftsphilosophie haben können. Mit der Economics of Scientific Knowledge (ESK) hat sich seit Mitte der 1990er Jahre ein Literaturzweig herausgebildet, in dem genau diese Zielsetzung verfolgt wird, nämlich das Erkenntnisobjekt der wissenschaftlichen Koordination mit unterschiedlichen Methoden und Instrumenten der Ökonomik zu untersuchen. Es wird gezeigt, dass den analytischen Modellen der ESK einige Probleme inhärent sind, die prinzipiell durch neue Methoden und Instrumente gelöst werden können. Als ein geeigneter Kandidat wird die Agentenbasierte Modellierung (ABM) identifiziert, die eine realitätsnähere Abbildung der Akteure, eine ergebnisoffene Modellierung ihrer Entscheidungen und des Koordinationsprozesses erlaubt. Der Analyse von der ESK zuzuordnenden analytischen und agentenbasierten Modellen folgt im zweiten Teil der Dissertation die Programmierung einer eigenen ABM Continuous Opinions of Satisficing Agents and Discrete Actions (COSDA) mit Hilfe der Multi-Agenten-Programmiersprache NetLogo. In der heuristischen ABM COSDA werden zentrale wissenschaftsphilosophische und ökonomische Prämissen, die im ersten Teil der Arbeit als Problemfelder identifiziert wurden, aufgegeben. Mit Modellierung heterogener Agententypen, die - mit unterschiedlichen Präferenzen und Verhaltensheuristiken ausgestattet - miteinander interagieren, wird eine mögliche Mikrospezifikation für die Emergenz eines Makrophänomens erzeugt. Das Makrophänomen, d.h. die unterschiedlichen Resultate im wissenschaftlichen Koordinationsprozess, sind aus den selbstverstärkenden Effekten der Interaktion erklärbar, aber nicht vorhersehbar. Die Mikrospezifikation kann als relevante, durch eine kohärente Fiktion formulierte Möglichkeit interpretiert werden, die anders als analytische Modelle der ESK kein rationales Entscheidungskalkül der Agenten voraussetzt

Perceptions of professional identity and interprofessional working in children's services

Little is known about how frontline professionals’ perceptions of identity and interprofessional working (IPW) impacts on their ability to work collaboratively. This study contributes to a better understanding of the role of professional identity in collaborative working through an exploration of the views of four professional groups; early years professionals, health visitors, police officers and social workers, who come together within the framework of the team around the child (TAC). The research adopted a mixed-methods design using a questionnaire (n=124) and semi-structured interviews (n=36). The questionnaires were analysed by comparing the mean ratings professionals gave to their own professional characteristics and the other three professions and the interviews were analysed using an interpretative phenomenological approach to gain more insight into professionals’ perceptions of their identity and experiences of working together. The findings revealed that the professionals had a good understanding of their differing status within collaborative working and sought to maintain their professional identity rather than adopting an interprofessional persona. Working together was not viewed as a joint enterprise and professionals questioned whether it was necessary to develop interprofessional relationships to work effectively. Despite stating that they generally worked well together professionals were quite critical of each other’s practice and blamed each other when things went wrong. Issues were raised about the efficacy of the TAC model in terms of the lead role, the quality of information sharing and discussion, and the fear of discord between professionals. The study highlights that professionals are not as committed to IPW as policy makers and organisations assume. There needs to be more awareness at all levels of the impact of professional identity, intergroup theory and a supportive environment on IPW. The mindset that dismisses the importance of professional relationships must be changed to enhance the development of trust between professionals. A reconfiguration of services with more opportunities for contact between professionals would support this. It is recommended that the TAC model is restructured with independent leadership, clear guidelines of professional responsibility and improved organisational support. Realistic group conflict theory could be used as a framework to help professionals acknowledge and manage conflict between them. Further research is recommended to develop a wider understanding of professionals’ perceptions of professional identity and IPW

A generic model of collectivities

A class of social phenomena, exhibiting fluid boundaries and constant change, called 'collectivities,' is modeled using an agent-based simulation, demonstrating how such models can show that a set of plausible microbehaviors can yield the observed macrophenomenon. Some features of the model are explored and its application to a wide range of social phenomena is described

A generic model of collectivities

A class of social phenomena, exhibiting fluid boundaries and constant change, called 'collectivities,' is modeled using an agent-based simulation, demonstrating how such models can show that a set of plausible microbehaviors can yield the observed macrophenomenon. Some features of the model are explored and its application to a wide range of social phenomena is described