Object Oriented Modeling Of Social Networks

The aim of this paper is to explain principles of object oriented modeling in the scope of modeling dynamic social networks. As such, the approach of object oriented modeling is advocated within the field of organizational research that focuses on networks. We provide a brief introduction into the field of social networks and present an overview of existing network modcls and methods. Subsequently wc introduce an clementmy problem field in thc social scicnces in gcncral, and in studies of organizational change and design in particular: the micro-macro link. We argue that the most appropriate way to handle this problem is the principle of methodological individualism. For social network analysis, to contribute to this theoretical perspective, it should include an individual choice mechanism and become more dynamically oriented. Subsequently, object oriented modeling is advocated as a tool to meet these requirements for social network analysis. We show that characteristics of social systems that are emphasized in the methodological individualistic approach have their direct equivalences in object oriented modeIs. The link between the micro level where actors act, and the macro level where phenomena occur as a consequence and cause of these actions, can be modelled in a straightforward way

Effect of Seven-Valent Pneumococcal Conjugate Vaccine on Staphylococcus aureus Colonisation in a Randomised Controlled Trial

Background: Heptavalent pneumococcal conjugate vaccine (PCV7) shifts nasopharyngeal colonisation with vaccine serotype pneumococci towards nonvaccine serotypes. Because of the reported negative association of vaccine serotype pneumococci and Staphylococcus aureus in the nasopharynx, we explored the effect of PCV7 on nasopharyngeal colonisation with S. aureus in children and parents. Methodology/Principal Findings: This study was part of a randomised controlled trial on the effect of PCV7 on pneumococcal carriage, enrolling healthy newborns who were randomly assigned (1: 1: 1) to receive PCV7 (1) at 2 and 4 months of age (2) at 2, 4 and 11 months or (3) no PCV7 (controls). Nasopharyngeal colonisation of S. aureus was a planned secondary outcome. Nasopharyngeal swabs were obtained from all children over a 2-year period with 6-months interval and from one parent at the child's age of 12 and 24 months and cultured for Streptococcus pneumoniae and S. aureus. Between July 2005 and February 2006, 1005 children were enrolled and received either 2-doses of PCV7 (n = 336), 2+1-doses (336) or no dose (n = 333) before PCV7 implementation in the Dutch national immunization program. S. aureus colonisation had doubled in children in the 2+1-dose group at 12 months of age compared with unvaccinated controls (10.1% versus 5.0%; p = 0.019). A negative association for co-colonisation of S. pneumoniae and S. aureus was observed for both vaccine serotype (adjusted odds ratio (aOR) 0.53, 95% confidence interval (CI) 0.38-0.74) and nonvaccine serotype pneumococci (aOR 0.67, 95% CI 0.52-0.88). Conclusions/Significance: PCV7 induces a temporary increase in S. aureus colonisation in children around 12 months of age after a 2+1-dose PCV7 schedule. The potential clinical consequences are unknown and monitoring is warranted

Strategic decision making

This paper introduces a methodology for strategic intervention in collective decision making.The methodology is based on (1) a decomposition of the problem into a few main controversial issues, (2) systematic interviews of subject area specialists to obtain a specification of the decision setting,consisting of a list of stakeholders with their capabilities, positions, and salience on each of the issues; (3) computer simulation. The computer simulation models incorporate only the main processes through which differences in positions and salience are accommodated in binding decisions: management of meaning through the provision of convincing information, challenges, and exchanges. The methodology generates insights into the likely outcomes of the process, the amount of conflict involved, and the stability of the outcomes.These insights and the investigation of the effects of strategic moves provide major strategic advantages to the user. This is likely to lead to a better representation of the user's own position in the decision outcomesnd the creation of a broader political and social support behind the decision outcom

Conflict measures in cooperative exchange models of collective decision-making

This study focuses on externalities of exchanges of voting positions in collective decision-making. Exchanges are represented by nonconstant two-person cooperative games. It is assumed that the rate of exchange is specified by the Raiffa-Kalai-Smorodinsky solution, and a model is specified to identify the exchanges. Externality effects of these exchanges are assessed with two conflict measures we develop here. The measures assess within-group and between-group conflict, respectively, and are applied to collective decision-making in the European Union regarding support for fishery infrastructure. The application shows that the measures provide indispensable insights into the decision-making setting and that these can be used for strategic intervention in the setting. It also shows that both actors' power and the outcomes in exchange with externalities are very different from those in exchange without externalities as studied by theories of network exchange