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Two major types of ensemble methods exist: while the first type is based on the idea of varying the training data (Boosting, Bagging), the second type tries to exploit information on each classifier΄s area of expertise (Grading, Delegating, Arbitrating). This paper presents a new ensemble method called partitioner trees that combines both approaches. Information on misclassifications is used to train meta classifiers called partitioners and to split training data into disjoint subsets. On these subsets succeeding specialised classifiers are constructed. This process yields a binary decision tree with partitioners on the inner nodes to perform the splitting and specialised local classifiers on the leaves for final classification. Partitioner trees are compared to five other ensemble methods in experiments on four different datasets. The results show that on large datasets partitioner trees have a similar classification accuracy as AdaBoost , and are superior to those of other meta classifier based ensemble methods. In addition, partitioner trees outperform most other ensemble methods in regard to training time and allow for adaptively tuning parameters. [ABSTRACT FROM AUTHOR]

This investigation evaluated the effectiveness of supplementing eight elite rugby league referees with a 6% maltodextrin (Md) solution whilst undertaking a simulated rugby league game. The simulation was based on motion analysis of six rugby league matches. Subjects undertook two trials of repetitive 20-m shuttle activity on an indoor track. During one trial 200 ml of Md was ingested at eight time points and in the other trial a similarly tasting placebo (Pl) was administered. A single-blind, counterbalanced design was employed. The simulation involved subjects performing four, 10-min blocks of shuttle activity before a 10-min break was instigated. Three further 10-min blocks of shuttle activity were also performed before a performance test to volitional exhaustion involving 20-m shuttles at paces varying between 55 and 95% of a pre-determined O2 max was undertaken. Timed 15-m sprints took place during each of the 10-min blocks. The rating of perceived exertion (RPE), and blood glucose and lactate concentrations were also determined throughout. The mean number of shuttles to exhaustion was significantly greater with Md ingestion than with Pl ingestion (57 ± 19 vs. 43± 15; p <0.05), while the mean 15-m sprint times were significantly shorter for the Md than the P1 condition (2.40±0.09 s vs. 2.51 ±0.14 5; p<0.01). The mean RPE was 5.2% lower during Md than Pl ingestion, the values being significantly different (Md: 12.07±0.32; P1: 12.73±0.28; p<0.01). Maltodextrin ingestion significantly elevated blood glucose levels compared with placebo (F(1,7) = 18.07: p < 0.01), although no significant differences were apparent for blood lactate levels (F(1,7) = 4.39; p >0.05). These results highlight the beneficial effects of maltodextrin ingestion on work-rates of rugby league referees in a simulation of a game's activity. The improvement may be related to higher circulating concentrations of blood glucose. [ABSTRACT FROM AUTHOR]

This document records the process and findings of an evaluation of the sport rage prevention kit and its impact on planning by sport club committees, adoption of sport rage prevention strategies, confidence of committees in dealing with sport rage incidents and perceived cultural change within sport clubs. [ABSTRACT FROM CONTRIBUTOR]