Effects of contrasting colour patterns of the ball in the volleyball reception

The effects of three different colour patterns on the surface of volleyballs (versus that of a plain white ball) on the behaviour of a reception player were examined by presenting sidespin volleyball serves. Expert (n = 10) and novice (n = 10) volleyball players intercepted volleyballs projected straight at them or at an initial angle of 9.5 degrees outwards but eventually curving towards the players' original position. In the latter trajectories, players generally took one or more steps laterally before returning to the landing position of the ball. These excursion patterns were significantly more pronounced with the white balls than the coloured balls. Differences between balls of different colour combinations were also observed. The first finding supports the thesis that next to a prospective type of control, such as on-line maintenance of a certain spatiotemporal relationship between the player and the ball, properties of the ball itself allow prediction of the future path of the ball. Differences between types of colour patterns are explained within the framework of the between-colours wavelength contrasts of each type of ball.     

New practices for electronic publishing 2: New forms of the scientific paper

We extend the analysis of our previous paper (Learned Publishing 2001: 265–72) to a broader discussion of the major features of electronic publications. We conclude that a distinctly different granularity of information will be required and that this will allow very different levels of authentication and quality control from those currently used for the traditional scientific paper.     

New practices for electronic publishing 1: Will the scientific paper keep its form?

Discussion about the value of electronic documents is often hampered by starting from what is usual in the paper world and attempting to impose that on an electronic environment. In order to grasp the impact of the current electronic revolution, and formulate a policy for the future, we examine the aims and content of scientific communication. We then critically discuss the recommendations of an International Working Group [see Learned Publishing 2000:13(4) Oct. 251–8], and show the tension between these very reasonable recommendations and the reality of electronic publishing. We conclude that the scientific article will change considerably but that, in its new more composite form as an ensemble of various textual and non-textual components, it will retain many of the current cultural and scientific requirements with regard to editorial, quality and integrity.     

Self-study packages: vantage points for a new instructional design

Instructional design is confronted with the need to take research outcomes of cognitive research into account. In this contribution a research-framework is presented as a first step toward the construction of a more encompassing cognitive instructional design model (CID-model). A strategy “ConStruct” is described which enables instructional designers to evaluate the structure of information in instructional texts from a cognitive point of view. This strategy is an example of the way in which cognitive research outcomes can be implemented in the design of printed self-study packages.