Game management, context effects, and calibration: the case of yellow cards in soccer

Referees in German first-league soccer games do not award as many yellow cards in the beginning of a game as should be statistically expected. One explanation for this effect is the concept of game management (Mascarenhas, Collins, & Mortimer, 2002). Alternatively, the consistency model (Haubensak, 1992) explains the effect as a necessity of the judgment situation: Referees need to calibrate a judgment scale, and, to preserve degrees of freedom in that scale, they need to avoid extreme category judgments in the beginning (i.e., yellow cards). Experiment 1 shows that referees who judge scenes in the context of a game award fewer yellow cards than referees who see the same scenes in random order. Experiment 2 shows the combined influence of game management (by explicitly providing information about the game situation) and calibration (early vs. late scenes in the time course of a game). Theoretical implications for expert refereeing and referee training are discussed.     

A Wittgenstein Approach to the Learning of OO-modeling

The paper uses Ludwig Wittgenstein's theories about the relationship between thought, language, and objects of the world to explore the assumption that OO-thinking resembles natural thinking. The paper imports from research in linguistic philosophy to computer science education research. I show how UML class diagrams (i.e., an artificial context-free language) correspond to the logically perfect languages described in Tractatus Logico-Philosophicus. In Philosophical Investigations Wittgenstein disputes his previous theories by showing that natural languages are not constructed by rules of mathematical logic, but are language games where the meaning of a word is constructed through its use in social contexts. Contradicting the claim that OO-thinking is easy to learn because of its similarity to natural thinking, I claim that OO-thinking is difficult to learn because of its differences from natural thinking. The nature of these differences is not currently well known or appreciated. I suggest how explicit attention to the nature and implications of different language games may improve the teaching and learning of OO-modeling as well as programming.     

The impact of participation in sports on educational attainment—New evidence from Germany

We analyze the impact of exercising sports during childhood and adolescence on educational attainment. The theoretical framework is based on models of allocation of time and educational productivity. Using the rich information from the German Socio-Economic Panel (GSOEP), we apply generalized ordered probit models to estimate the effect of participation in sport activities on secondary school degrees and professional degrees. Even after controlling for important variables and selection into sport, we find strong evidence that the effect of sport on educational attainment is statistically significant and positive.     

Efficient reverse k-nearest neighbor estimation

The reverse k-nearest neighbor (RkNN) problem, i.e. finding all objects in a data set the k-nearest neighbors of which include a specified query object, has received increasing attention recently. Many industrial and scientific applications call for solutions of the RkNN problem in arbitrary metric spaces where the data objects are not Euclidean and only a metric distance function is given for specifying object similarity. Usually, these applications need a solution for the generalized problem where the value of k is not known in advance and may change from query to query. In addition, many applications require a fast approximate answer of RkNN-queries. For these scenarios, it is important to generate a fast answer with high recall. In this paper, we propose the first approach for efficient approximative RkNN search in arbitrary metric spaces where the value of k is specified at query time. Our approach uses the advantages of existing metric index structures but proposes to use an approximation of the nearest-neighbor-distances in order to prune the search space. We show that our method scales significantly better than existing non-approximative approaches while producing an approximation of the true query result with a high recall.     

Continuous usage of e-participation: The role of the sense of virtual community

Local governments around the world are increasingly implementing e-participation platforms to involve citizens in consultation and decision-making processes. E-participation platforms usually succeed and produce positive effects in the community when adopted in the long-term scenario. The adoption of those platforms is still a challenge for local governments. The understanding of the factors that influence the continuous intention to use e-participation over time is critical for the design of diffusion and promotion strategies that motivate the citizens to keep using e-participation. This article explores the drivers that predict the post-adoption of e-participation platforms from the perspective of the sense of virtual community theory, that is the degree of affective attachment to a given community mediated by information technology. Specifically, our research model evaluates the association between the sense of virtual community with use behaviour and the continuous intention to use e-participation. Structural equation modelling was used to evaluate the data collected from 370 citizens who experienced an e-participation platform hosted by a European capital city. We found out that the direct association between the sense of virtual community and use was significant. Even though the direct association between the sense of virtual community and the continuous intention was non-significant, the indirect association sense of virtual community to use to continuous intention was statistically significant. This finding may indicate that the use behaviour is triggered by the influence of other members of the community for a short period of time, but it does not persist to influence the continuous intention over time.