Rolf Arnold, Sigrid Nolda, Ekkehard Nuissl (Hg.): Wörterbuch der Erwachsenenpädagogik

Ohne Zusammenfassung     

Group sequential tests for treatment effect on survival and cumulative incidence at a fixed time point

Lifetime Data Analysis - Medical research frequently involves comparing an event time of interest between treatment groups. Rather than comparing the entire survival or cumulative incidence curves,...     

Comparison of prediction methods for multicollinear data

In this paper we discuss the partial least squares (PLS) prediction method. The method is compared to the predictor based on principal component regression (PCR). Both theoretical considerations and computations on artificial and real data are presented.     

Explaining Attitudes towards Self-employment among Immigrants: A Canadian Case Study

Implicit in Canada's immigration policies is that some immigrants are endowed with a particular entrepreneurial spirit, and that this spirit relates to immigrants’ origin. This paper examines whether attitudes towards entrepreneurship indeed relate to origin, or whether they can be explained through labour market circumstances at the place of settlement and/or Canada's immigrant selection procedure. The empirical study focuses on the reported attitudes towards entrepreneurship. A survey of 509 Vancouver residents of a predominantly Chinese immigrant neighbourhood, a predominantly South Asian immigrant neighbourhood, and a neighbourhood of non‐immigrants reveals that ethnic origin is a weak indicator of entrepreneurial attitudes. Instead, urban or rural background emerges as a more powerful predictor. The results also raise doubts about whether the Canadian government's immigration policy, which selects immigrants on the basis of economic potential, indeed selects immigrants with a greater desire to become self‐employed. Furthermore, the amount of time immigrants have spent in Canada does not significantly affect attitudes towards entrepreneurship.     

Roof–envelope ratio impact on green roof energy performance

This paper addresses the impact of roof-to-envelope ratio on overall energy savings of a green roof design over conventional roof designs. Simulations were performed using a modified version of the Environmental System Performance program simulator, developed at the University of Strathclyde. The modified design employed a model developed by Columbia University and the Goddard Institute of Space Science which models the evapotranspiritive effect of a green roof calculated using the Bowen ratio; that is, the ratio of sensible heat flux to the surrounding air to the latent heat flux resulting from evapourative energy losses. The resulting heat flux term is proportional to the external surface convection, but inversely proportional to the surface Bowen ratio, which is held constant and chosen to match experimental results obtained for a given roof design. The present study performed simulations for the month of July in a Toronto climate on square warehouse style one, two, and three-story buildings, with windows occupying 10% of the area of each wall. For the first set of simulations, the internal building load of each story was set to zero, and the roof–envelope ratio was increased by increasing the building width and length. For the final simulations, several roof–envelope ratios were chosen, and the internal load of each story was increased from 0 to 50,000 W. As the roof–envelope ratio increases, the cooling load of the upper floor for multi-story designs approaches the entire building cooling load. This indicates the importance of upper zone cooling in total building energy reductions. Furthermore, the total energy savings of a green-roofed building over a conventional roofed building were far more significant for single-story structures. A 250 × 250 m green-roof design with 50,000 W internal loading was found to have percentage energy savings of 73%, 29%, and 18%, for a one, two, and three-story design, respectively.     

The Recurrence of Violence

This article examines the recurrence of violence in the contemporary world based on the premise that states can use their monopoly of violence not only for preserving the life of their citizens but also for the sake of terror and annihilation. This ambiguous nature of the use of violence derives from the fact that the legal order of the state is a function of concrete acts of bloodshed and killing. The state bases the law on violence because authorities fear the psychological attraction that bloodshed has on the human imagination. The contagious character of violence, however, is not based on man's innate potential for aggression. Rather, it depends on the nature of the reciprocity of social relations. Violent conflict often feeds on negative social communication such as hatred and desire for vengeance. Yet, faced with the inevitable recurrence of violence humans have the capacity to act on the spiral of vengeance. One possible way to pacify violence is to transform the destructive, negative reciprocity of retaliation into the creative, positive reciprocity of active non-violence.