From Microactions to Macrostructure and Back: A Structurational Approach to the Evolution of Organizational Networks

Structuration theory (ST) and network analysis are promising approaches for studying the emergence of communication networks. We offer a model that integrates the conceptual richness of structuration with the precision of relevant concepts and mechanisms offered from communication network research. We leverage methodological advancements (i.e., stochastic actor‐oriented models) to test hypotheses deduced from ST using longitudinal communication network data collected over a two‐year period. Results indicate that while structural rules external to a social network play a significant role, internal structural rules that emerge from the aggregate of individual actions during previous time periods also predict current structures, and that the reification influence of the latter is greater than that of the external factors.     

Media use and school achievement – boys at risk?

In work done at the German Criminological Research Institute of Lower Saxony (KFN) various methods have been used to investigate how specific inappropriate media usage patterns affect academic performance in children and adolescents. The findings are paralleled by current international research indicating a negative relationship between these two variables. Based on a cross‐sectional survey of 5,529 fourth grade students and a longitudinal panel study with 1,157 primary schoolchildren, a key finding can be demonstrated: the more time students spend on consuming media and the more violent its contents are, the worse are their marks at school, even when controlling for vital factors such as family, educational, or immigrant background. In particular, boys who gender‐specifically are better equipped with electronic media devices, who partially have extensive media usage times and who strongly prefer violent media content, are at the risk of showing poor school performance. In fact, a decrease in academic performance of boys can be observed in German school statistics. By presenting first results of a school‐based intervention programme, a promising approach to the reduction of detrimental effects of electronic media use on school performance is introduced.     

Labeled Calculi and Finite-Valued Logics

A general class of labeled sequent calculi is investigated, and necessary and sufficient conditions are given for when such a calculus is sound and complete for a finite-valued logic if the labels are interpreted as sets of truth values (sets-as-signs). Furthermore, it is shown that any finite-valued logic can be given an axiomatization by such a labeled calculus using arbitrary "systems of signs," i.e., of sets of truth values, as labels. The number of labels needed is logarithmic in the number of truth values, and it is shown that this bound is tight.