Visualising collaboration via email: Finding the key players

Email is an important form of asynchronous communication. Visualizing analyses of email communication patterns during a collaborative activity help us better understand the nature of collaboration, and identify the key players. By analysing the contents of email communication and adding reflective comments on its perceived importance from the participants of a collaboration new information can be gleaned not immediately obvious in its original flat form. This paper outlines a proof-of-concept prototype collaborative email visualisation schema. Data from a collaboration case study is analysed and subsequently employed to construct a display of the relative impact of both key players and the types of email used.

Classifying an opponent's behaviour in robot soccer

This paper illustrates the prediction of opponent behaviour in a competitive, highly dynamic, multi-agent and partially observableenvironment, namely RoboCup small size league robot soccer. The performance is illustrated in the context of the highly successful robot soccer team, the RoboRoos. The project is broken into three tasks; classification of behaviours, modelling and prediction of behaviours and integration of the predictions into the existing planning system. A probabilistic approach is taken to dealing with the uncertainty in the observations and with representing the uncertainty in the prediction of the behaviours. Results are shown for a classification system using a Naïve Bayesian Network that determines the opponent’s current behaviour. These results are compared to an expert designed fuzzy behaviour classification system. The paper illustrates how the modelling system will use the information from behaviour classification to produce probability distributions that model the manner with which the opponents perform their behaviours. These probability distributions are show to match well with the existing multi-agent planning system (MAPS) that forms the core of the RoboRoos system.

Expertise and the perception of kinematic and situational probability information

Two experiments were conducted on the nature of expert perception in the sport of squash. In the first experiment, ten expert and fifteen novice players attempted to predict the direction and force of squash strokes from either a film display (occluded at variable time periods before and after the opposing player had struck the ball) or a matched point-light display (containing only the basic kinematic features of the opponent's movement pattern). Experts outperformed the novices under both display conditions, and the same basic time windows that characterised expert and novice pick-up of information in the film task also persisted in the point-light task. This suggests that the experts' perceptual advantage is directly related to their superior pick-up of essential kinematic information. In the second experiment, the vision of six expert and six less skilled players was occluded by remotely triggered liquid-crystal spectacles at quasi-random intervals during simulated match play. Players were required to complete their current stroke even when the display was occluded and their prediction performance was assessed with respect to whether they moved to the correct half of the court to match the direction and depth of the opponent's stroke. Consistent with experiment 1, experts were found to be superior in their advance pick-up of both directional and depth information when the display was occluded during the opponent's hitting action. However, experts also remained better than chance, and clearly superior to less skilled players, in their prediction performance under conditions where occlusion occurred before any significant pre-contact preparatory movement by the opposing player was visible. This additional source of expert superiority is attributable to their superior attunement to the information contained in the situational probabilities and sequential dependences within their opponent's pattern of play.

Simultaneous pooled auctions

Suppose a seller wants to sell k similar or identical objects and there are n > k potential buyers. Suppose that each buyer wants only one object. In this case, we suggest the use of a simultaneous auction that would work as follows. Players are asked to submit sealed bids for one object. The individual with the highest bid chooses an object first; the individual with the second-highest bid chooses the next object; and this process continues until the individual with the kth highest bid receives the last object. Each individual pays the equivalent to his or her bid. When objects are identical, we show that the proposed auction generates the same revenue as a first-price sealed-bid sequential auction. When objects are perfectly correlated, there is no known solution for sequential auctions, whereas we can characterize bidding strategies in the proposed auction. Moreover, the proposed auction is optimal (given an appropriately chosen reserve price), and it may be easier and cheaper to run than a sequential auction.

Concussion in contact sports: Reliable change indices of impairment and recovery

This paper reports a follow-up study to an article on the sensitivity of three tests of speed of information processing to impairment after concussion (Hinton-Bayre, Geffen, BL McFarland, 1997). Group analyses showed that practice effects can obscure the effects of concussion on information processing, thereby making the assessment of functional impairment and recovery after injury unreliable. A Reliable Change Index (RCI) was used to assess individual variations following concussion. It was found that 16 of the 20 concussed professional rugby league players were impaired 1-3 days following injury. It was also demonstrated that 7 players still displayed cognitive deficits at 1-2 weeks, before returning to preseason levels at 3-5 weeks. The RCI permits comparisons between different tests, players, and repeated assessments, thereby providing a quantitative basis for decisions regarding return to play.

Auctions with synergies and asymmetric buyers

In this paper we consider sequential auctions with synergies where one player wants two objects and the remaining players want one object each. We show that expected prices may not necessarily decrease as predicted by Branco [Econ. Lett. 54 (1997) 159]. Indeed we show that expected prices can actually increase. (C) 2004 Elsevier B.V All rights reserved.

Presentation and mechanisms of concussion in professional Rugby League football

The present study prospectively recorded the circumstances, incidence, mechanisms, injury detection and presentation of concussion in Rugby League. Forty-three consecutive concussions were recorded over three competitive seasons in 175 professional Rugby League players. Data showed (i) the incidence of concussion ranged from 5.9 to 9.8 injuries/1000 player hours across grades - except when age-group players were mismatched (18.4); (ii) 'head-high tackles' accounted for a significant number of concussions; (iii) concussion rarely involved a loss of consciousness with the most common indicators of concussion being amnesia, headache and unsteadiness, with the mechanism of injury often missed; and (iv) concussion often occurs concurrently with other injuries. Concussion (including repeated episodes) is a common injury in Rugby League. Systematic mental status questioning is warranted whenever concussion is suspected. Coaches, trainers and players need more education in the recognition and management of concussion. Stricter penalties for illegal 'head-high' tackling are strongly recommended.

B, NK and NKT cells contribute to suppression of immunity by dendritic cells

Among the population of antigen presenting cells, dendritic cells (DCs) are considered the sentinels of the immune system. Besides activating naı¨ ve T cells, DC can directly activate naı¨ ve and memory B cells and are also able to regulate effectors of innate immunity such as NK cells and NKT cells. Increasing evidence indicates that DCs are not only decisive for T cell priming, but are also key players to maintain self-tolerance in vivo. Previous results in our lab have shown that DCs treated with a pharmacological NFkB inhibitor (BAY11–7082) confer suppression to a previously immune response. This suppression was IL-10 dependent and results from the induction of Ag specific CD4+ regulatory T cells. To elucidate the mechanism of suppression induced by administration of Bay treated DC, we used a model of infectious tolerance transfer from DC treated mice to primed recipient mice. Our results show that both CD4 + splenic cells and non T cells from animals injected with Bay treated DC, but not from untreated DC, were capable of transferring the suppression. Moreover, sorted B cells and NK cells could transfer antigenspecific infectious tolerance after administration of Bay treated DC. In addition, this suppressive effect could not be seen either in mice depleted of NK cells nor in NKT deficient mice. These observations highlight the role of several immune cells in the maintenance of tolerance, and impact on the design of immunotherapeutic suppression of autoimmune diseases in which NKT cells are deficient or defective, such as diabetes and lupus.

Computer technology - A political player in social policy processes

The absence of considerations of technology in policy studies reinforces the popular notion that technology is a neutral tool, Through an analysis of the role played by computers in the policy processes of Australia's Department of Social Security, this paper argues that computers are political players in policy processes, Findings indicate that computers make aspects of the social domain knowable and therefore governable, The use of computers makes previously infeasible policies possible, Computers also operate as bureaucrats and as agents of client surveillance. Increased policy change, reduced discretion and increasingly targeted and complex policies can be attributed to the use of computer technology, If policy processes are to be adequately understood and analysed, then the role of technology in those processes must be considered.