Multidimensional adaptive testing in educational and psychological measurement: Current state and future challenges

The paper gives an overview of multidimensional adaptive testing (MAT) and evaluates its applicability in educational and psychological testing. The approach of Segall (1996) is described as a general framework for MAT. The main advantage of MAT is its capability to increase measurement efficiency. In simulation studies conceptualizing situations typical to large scale assessments, the number of presented items was reduced by MAT by about 30–50% compared to unidimensional adaptive testing and by about 70% compared to fixed item testing holding measurement precision constant. Empirical results underline these findings. Before MAT is used routinely some open questions should be answered first. After that, MAT represents a very promising approach to highly efficient simultaneous testing of multiple competencies.     

Acute exercise-induced irisin release in healthy adults: Associations with training status and exercise mode

There is a growing interest in exploring irisin response to acute exercise; however, the associations of acute exercise-induced irisin release with training status and exercise mode are not fully understood. This study was primarily designed to evaluate these associations. Sixteen healthy adults (8 trained versus 8 untrained) underwent a bout of cycling at 80% of maximal oxygen uptake (VO_2max) for 50?min, with blood drawn pre-, 10-, and 180-min post-exercise. Another 17 healthy adults performed 2 bouts of graded exercise (cycling and running) until exhaustion on separate days using a randomized cross-over design, with blood taken pre-, 0-, 10-, and 60-min post-exercise. Circulating irisin, creatine kinase (CK), aspartate aminotransferase (AST), and myoglobin (Mb) were measured, and their respective areas under the curves (AUCs) were calculated. Irisin increased 10-min after 50?min of cycling at 80% of VO_2max, while its changes from baseline to post-exercise and the amount of exercise-induced irisin release (presented as AUC) were comparable between trained and untrained adults (all P?>?.05). Irisin remained elevated 10-min post-exhausting running but decreased towards baseline 10-min post-exhausting cycling. Exhausting running induced an increase in irisin release for the whole course of exercise and recovery periods, but cycling did not. Acute exercise-induced irisin changes seemed not related to changes of CK, aspartate AST, and Mb in general. In conclusion, acute exercise-induced irisin release is not associated with training status but might be affected by training mode. Future studies are required to investigate which exercise mode might be most efficient in altering irisin.     

Prognostic validity of talent orientation in soccer

Several talent-screening programs conducted within elementary schools have implemented motor diagnostics to introduce children to groups of sports including both game and specific sports, the latter of which includes gymnastics, skiing, and tennis. However, as in most other sports, the predictive value for soccer regarding such early testing is unclear. This prospective cohort study evaluated the mid-term prognostic validity of general motor tests as well as a soccer-specific score calculated from a test battery. The sample consisted of N?=?2965 U9 age group of children from the Fulda Movement Check (FMC). The FMC is a basic check comprised of two anthropometric parameters and eight general items of the German Motor Test 6–18 by Boes and Schlenker with the addition of a ball throw. The test data were collected from the second grade classes of 2011–2014. The soccer competition performance of those children who chose soccer (n?=?316) up to the end of the season 2016/17 (September 30, 2017) was recorded. This group of U12–U15 players was then assigned individually to four different competition levels. The prognostic validity of the motor tests was determined using analysis of variance, odds ratios, and a discriminant analysis. All diagnostic methods exhibited medium to high prognostic validity over the 2? to 6?year time span from the talent screening and talent orientation period to the later soccer competitions in the early adolescent U12–U15 age groups. The prognostic relevance of the nine general motor tests was confirmed.     

What has the Trolley Dilemma ever done for us (and what will it do in the future)? On some recent debates about the ethics of self-driving cars

Self-driving cars currently face a lot of technological problems that need to be solved before the cars can be widely used. However, they also face ethical problems, among which the question of crash-optimization algorithms is most prominently discussed. Reviewing current debates about whether we should use the ethics of the Trolley Dilemma as a guide towards designing self-driving cars will provide us with insights about what exactly ethical research does. It will result in the view that although we need the ethics of the Trolley Dilemma as important input for self-driving cars, the route towards simply implementing it into automated cars is blocked.     

Extreme case learning: the manager perspective on rare knowledge and capabilities development

International strategy is enhanced by organizations’ ability to learn in host markets; yet, it remains ambiguous how post-entry knowledge gaps between home – and host country shape MNE’s absorptive capacity. This article builds on the specific contributions of ‘extreme case’ internationalization to advance literature in this field. We foster the understanding of the role of rare knowledge and the mechanisms that link knowledge acquisition to absorptive capacity dynamics used in the internationalization path of multinational enterprises (MNEs). We opt for in-depth qualitative research into the post-entry phase of ‘extreme’ (thus particularly crude) international joint venture (IJV) investment, and analyze the perspective of managers from a developed economy MNE located in a high-risk, weak-institutions host country. The firm’s absorptive capacity and its interaction with external environments that are categorized into four distinct contexts are found to be contingent upon pro-active experiential learning, concurrent to managerial willingness and simultaneous organizational commitments to learning and to exploiting rare knowledge. We thus uncover managerial perceptions of a knowledge gap identified as host-country challenges and resulting managerial solutions, which reveal rare learning opportunities and knowledge exploitation dynamics. The capacity to compensate for knowledge gaps is a critical key within the design and consolidation of an alternative internationalization path for developed-country MNEs. This challenges the traditional risk–return–commitment dependencies in prior literature.     

Datenbank-Caching - Eine systematische Analyse m?glicher Verfahren

Caching ist ein bewährtes Mittel, um die Skalier- und Verfügbarkeit von Systemen zu steigern sowie die Latenzzeit für Benutzeranforderungen zu verkürzen. Im Gegensatz zum Web-Caching, bei dem einzelne Web-Objekte irgendwo längs ihres Aufrufpfades in der Proxy-Kette vorgehalten werden, setzt Datenbank-Caching ausgewachsene Datenbanksysteme als Caches ein, um dort Satzmengen entfernter Datenbanken möglichst adaptiv verwalten und Anfragen darauf auswerten zu können. Verfahren dazu reichen von separat verwalteten materialisierten Sichten über überlappende, aber replikationsfrei gespeicherte Sichten bis hin zu Cache-Groups, in denen parametrisierte Cache-Constraints den Cache-Inhalt spezifizieren. Wir untersuchen anschaulich die verschiedenen Ansätze und ermitteln daraus eine Klassifikation, die den Lösungsraum zu enthüllen hilft. Im Mittelpunkt steht das Konzept der Prädikatsvollständigkeit: Ein Datenbank-Cache verwaltet vollständige Extensionen von Prädikaten, was ihm ermöglicht, Schlüsse über beantwortbare Anfragen zu ziehen.     

Astronomical broadsheets and their scientific significance

For more than three centuries broadsheets were an important means of quickly disseminating and commenting on the news of the day. They depicted a wide range of events of historical significance, including some of the more striking celestial phenomena such as the appearance of comets. Those that survive often do no more than repeat knowledge that can readily be gained from conventional sources but some have proved of direct value in making astronomical computations and deductions.