PIRUS2: individual article usage statistics — developing a practical,global standard

The most granular level at which COUNTER currently requires reporting of usage is for the individual journal. A number of developments have, however, meant that it is now practical to investigate the development of a COUNTER standard for the recording, reporting, and consolidation of usage statistics at the individual article level. The aim of PIRUS2 (Publisher and Institutional Repository Usage Statistics 2) was to take forward the outcomes of the original PIRUS project and build on its recommendations, by developing a prototype service (including technical, organizational, and economic models) that will enable publishers, repositories, and other organizations to generate and share authoritative, trustworthy usage statistics for the individual articles and other items that they host. The PIRUS2 project was completed in June 2011. This article covers the aims, objectives, outputs and recommendations of the project.     

COUNTER 2005: a new Code of Practice and new applications of COUNTER usage statistics

The article gives an update on the progress with COUNTER to May 2005. In particular it describes the draft Code of Practice for books and reference works and the results of actual use of COUNTER‐compliant data in the journals area.     

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.     

Confirmatory factor analysis of the Test of Performance Strategies (TOPS) among adolescent athletes

The aim of the present study was to examine the factorial validity of the Test of Performance Strategies (TOPS; Thomas et al., 1999) among adolescent athletes using confirmatory factor analysis. The TOPS was designed to assess eight psychological strategies used in competition (i.e. activation, automaticity, emotional control, goal-setting, imagery, negative thinking, relaxation and self-talk,) and eight used in practice (the same strategies except negative thinking is replaced by attentional control). National-level athletes (n = 584) completed the 64-item TOPS during training camps. Fit indices provided partial support for the overall measurement model for the competition items (robust comparative fit index = 0.92, Tucker-Lewis index = 0.88, root mean square error of approximation = 0.05) but minimal support for the training items (robust comparative fit index = 0.86, Tucker-Lewis index = 0.81, root mean square error of approximation = 0.06). For the competition items, the automaticity, goal-setting, relaxation and self-talk scales showed good fit, whereas the activation, emotional control, imagery and negative thinking scales did not. For the practice items, the attentional control, emotional control, goal-setting, imagery and self-talk scales showed good fit, whereas the activation, automaticity and relaxation scales did not. Overall, it appears that the factorial validity of the TOPS for use with adolescents is questionable at present and further development is required.