Result merging methods in distributed information retrieval with overlapping databases

In distributed information retrieval systems, document overlaps occur frequently among different component databases. This paper presents an experimental investigation and evaluation of a group of result merging methods including the shadow document method and the multi-evidence method in the environment of overlapping databases. We assume, with the exception of resultant document lists (either with rankings or scores), no extra information about retrieval servers and text databases is available, which is the usual case for many applications on the Internet and the Web. The experimental results show that the shadow document method and the multi-evidence method are the two best methods when overlap is high, while Round-robin is the best for low overlap. The experiments also show that [0,1] linear normalization is a better option than linear regression normalization for result merging in a heterogeneous environment.

Becoming More Reflective about the Role of Design in Communication

Robert Craig's constitutive meta-model of communication reminds us that while communication scholarship may feel like discovery of communication's natural properties, it is also often (if not always) on a path to invention of new possibilities and reconstitution. The constitutive meta-model suggests that every theory of communication is also a design language for communication, and that design itself may be a path to theory development. Design inquiry can be conducted in all subdisciplines of communication, incorporating and contributing to widely disparate communication theories. Design work itself takes many forms, producing artifacts as diverse as individual messages, persuasive campaigns, interaction protocols, large-scale participation frameworks for public decision-making, and more. This special issue explores design scholarship in the field of communication, with five original essays representing different subfields and different theoretical approaches. In this introduction, we argue that design work is more than application of theory; design itself is a theory-building enterprise. It is a distinct form of inquiry that builds new knowledge, complementary to, but different in kind from, empirical and critical scholarship.     

Copyright and licensing — the changing scene

A rapid survey of the key current issues and changes in the copyright and licensing environment. Briefly discusses the reasons why there is so much change, and in particular the changing attitudes of both authors and customers towards publishers. Surveys the new contractual problems confronting publishers; the requirements for doing business electronically in future; major legal changes; and developments in licensing. Concludes by considering how publishers can influence what happens.     

Listening to our Students: Understanding the factors that affect Aboriginal and Torres Strait Islander students' academic success

While the number of Aboriginal and Torres Strait Islander students in higher education in Australia has doubled in recent years, the gap between their attainment and the attainment of other Australians has remained consistent. It is essential to elucidate the factors that promote Aboriginal and Torres Strait Islander students' academic success, not in order to justify the exclusion of these students from tertiary education, but to refine and develop curriculum and management strategies which promote their academic success. This study focuses on Aboriginal and Torres Straight Islander students' experiences in a diploma program offered in block mode, in order to better understand the ‘on-’ and ‘off-’ campus experiences which are related to academic success and the factors which challenge or enhance students' study. The research yields important findings related to students' motivations to enrol and their definitions of academic success; the challenges they experience in making the transition to tertiary study; the vulnerability of our students' determination to succeed; the effects of being in a program for Aboriginal and Torres Strait Islander students; and the ways in which minor challenges, if unresolved, can accumulate to interfere with students' study.     

The role of stimulus salience in young children's ability to discriminate two-dimensional rotations: Reflections on a paradigm

Children's ability to discriminate reflections and rotations of visual stimuli was examined within the confines of a mental rotation task. It was hypothesized that success would be affected by both characteristics of the stimulus and by the subtlety of the discrimination required. Forty 3- to 4-year-old children were directed to mentally rotate a stimulus a given number of degrees and to discriminate the appearance of the rotated stimulus from among a set of alternatives. Four stimuli differing in the number of visual orientation cues were utilized across 24 trials. A significant effect was found for number of orientation cues, and data indicated the difficulty children experienced detecting reflections, a task which bears close resemblance to the yes/no option in prototypic rotation studies. Children were only successful with a limited range of stimuli when discrimination of a reflected foil was not required. Results are discussed in light of discrepant findings about children's kinetic imagery ability and the advisability of using this particular paradigm with young Children.     

Critical action learning: a method or strategy for peer supervision of coaching practice

This paper deals with the on-going practice of a critical action learning set who come together to meet their needs for coaching supervision as a group of executive coaches working from, and within, the University sector in South Wales. The reasons for the successes of, and the challenges around, this practice of four years standing have been articulated using an academic backdrop. The use of multi-factorial supervision has been heralded as being able to give a more rounded form of supervision which, despite its challenges, has, in this example, stood the test of time. Further data are required to try to understand if this form of supervision provides better coaching to the executive field in South Wales and beyond, and what can be learnt from the practice of supervision in general.     

Understanding Differences in Academic Effectiveness: Practitioners’ Views∗

As part of a large‐scale study of the ability of 94 secondary schools to promote academic achievement, case studies of six outlier schools were conducted and headteachers (principals) and their deputies were questioned about the processes of effectiveness. The analysis of their responses ‐ grouped by the performance of their school (measured by value added analyses of three years of public examination results) as effective, ineffective or mixed ‐ reveals considerable support for previously cited characteristics of effective schooling. Despite the limitations imposed by a reliance on the use of retrospective accounts, the study takes forward the field of school effectiveness in its search for generalisable findings and coherent theory.