On use of student samples for scale construction

This research note responds to the question of whether a convenience sample of undergraduate students may be successfully utilized in concept development and in scale construction, and in what way the results are comparable to the findings of a representative national sample. The results of a Mokken analysis in both samples support the hypothesis that convenience samples have utility in concept development and in developing measures that can also be used in representative samples.     

Neuroimaging techniques for memory detection: scientific, ethical, and legal issues

There is considerable interest in the use of neuroimaging techniques for forensic purposes. Memory detection techniques, including the well-publicized Brain Fingerprinting technique (Brain Fingerprinting Laboratories, Inc., Seattle WA), exploit the fact that the brain responds differently to sensory stimuli to which it has been exposed before. When a stimulus is specifically associated with a crime, the resulting brain activity should differentiate between someone who was present at the crime and someone who was not. This article reviews the scientific literature on three such techniques: priming, old/new, and P300 effects. The forensic potential of these techniques is evaluated based on four criteria: specificity, automaticity, encoding flexibility, and longevity. This article concludes that none of the techniques are devoid of forensic potential, although much research is yet to be done. Ethical issues, including rights to privacy and against self-incrimination, are discussed. A discussion of legal issues concludes that current memory detection techniques do not yet meet United States standards of legal admissibility.     

Rethinking free, libre and open source software

This special issue includes seven articles that make significant contribution to the literature pertaining to knowledge and public policy around Free, Libre and Open Source Software (FLOSS). Focusing on questions in two themes (i) motivation and organization and (ii) public policy, the articles in this volume develop new analytic models and report on new empirical findings, as an important step in bridging the wide gap that exists in public policy literature around FLOSS. Warning against rhetorical pitfalls that have been prevalent in FLOSS research, this introduction starts with a short history of FLOSS development, continues with a brief thematic literature review and review of the misconceptions surrounding FLOSS, and concludes with a first introduction of the articles that follow. He is part of the Dutch Institute of Government (NIG), the research school for public administration and political science. His research focuses on the organization of open source communities. He received two grants from the Netherlands Organization for Scientific Research (NWO) for research related to open source communities. The first grant was to study the interplay between intellectual property rights and open source communities. The results are published in Governing the Virtual Commons (Cambridge University Press, 2003). He has written numerous articles on open source, which have appeared in journals like Electronic Markets; Knowledge, Technology and Policy; and the International Journal of IT Standards & Standardisation Research. She received her Ph.D. in sociology from the University of York (UK) in 2004. Her Ph.D. research investigated the heterogeneity and contingency in the Free, Libre Open Source Software (FLOSS) social worlds, which is based on a constellation of hacking practices, from the sociological perspective. Her principal research interests center on FLOSS studies, Science and Technology Studies (STS), virtual communities and knowledge-sharing. Shay is also a fellow at The Information Society Project at the Yale Law School. Shay holds a B.Sc. in computer science and a B.A. in philosophy, magna cum laude, from Tel-Aviv University, and an M.A. from New York University where his interdisciplinary research thesis focused on the political economy of free and open source software and file sharing networks. Shay is an entrepreneur that co-founded two software start-up companies, and was involved for several years in cutting edge software research, combining open source and proprietary software.     

Strategic Maneuvering: A Synthetic Recapitulation

As an introduction to the special issue on Perspectives on Strategic Maneuvering, this article provides a synthetic recapitulation of the various steps that were taken in developing the pragma-dialectical theory of strategic maneuvering. First, the concept of strategic maneuvering is described as a means to reconcile the simultaneous pursuit of dialectical and rhetorical aims. Second, strategic maneuvering is related to the various kinds of argumentative activity types in which it takes place. Third, the concept of dialectical profiles is discussed and the parameters that are pertinent to distinguishing between different types of strategic maneuvering. Fourth, the fallacies are viewed as derailment of strategic maneuvering. Fifth, as a case in point, strategic maneuvering with inconsistency is examined. This contribution brings together insights that earlier were put forward in a number of separate publications.     

Walking on music

The present study focuses on the intricate relationship between human body movement and music, in particular on how music may influence the way humans walk. In an experiment, participants were asked to synchronize their walking tempo with the tempo of musical and metronome stimuli. The walking tempo and walking speed were measured. The tempi of the stimuli varied between 50 and 190 beats per minute. The data revealed that people walk faster on music than on metronome stimuli and that walking on music can be modeled as a resonance phenomenon that is related to the perceptual resonance phenomenon as described by Van Noorden and Moelants (Van Noorden, L., & Moelants, D. (1999). Resonance in the perception of musical pulse. Journal of New Music Research, 28, 43-66).     

The visual light field

Human observers are sensitive to the '(physical) light field' in the sense that they have expectations of how a given object would appear if it were introduced in the scene in front of them at some arbitrary location. Thus the 'visual light field' is defined even in the 'empty space' between objects. In that sense the light field is akin to visual space considered as a 'container'. The visual light field at any given point can be measured in psychophysical experiments through the introduction of a suitable 'gauge object' at that position and letting the observer adjust the appearance of that gauge object (eg through suitable computer rendering) so as to produce a 'visual fit' into the scene. The parameters of the rendering will then be considered as the measurement result. We introduced white spheres as gauge objects at various locations in stereoscopically presented photographic scenes. We measured the direction ('direction of the light'), diffuseness ('quality of the light' as used by photographers and interior decorators), and intensity of the light field. We used three very different scenes, with very different physical light fields. The images were geometrically and photometrically calibrated, so we were in a position to correlate the observations with the physical 'ground truth'. We report that human observers are quite sensitive to various parameters of the physical light field and generally arrive at close to veridical settings, although a number of comparatively minor systematic deviations from veridicality can be noted. We conclude that the visual light field is an entity whose existence is at least as well defined as that of visual space, despite the fact that the visual light field hardly appears as prominently in vision science as it does in the visual arts.     

What Research Has to Say About Gender-Linked Differences in CMC and Does Elementary School Children’s E-mail Use Fit This Picture?

This paper first reviews the literature on computer mediated communication (CMC) to examine whether claims about gender-linked differences in specific attitudes, styles and content in CMC have been validated. Empirical studies were limited, with considerable variation in audiences, tasks, and contexts that was related to varied outcomes. The paper next describes an empirical study on the e-mail communication of elementary school children from ten Dutch classrooms. No gender-linked preference for a person or task-oriented attitude was found. Girls significantly more often employed an elaborate style. Differences between boys and girls on content of communication were subtle rather than robust. The conclusion discusses the functional embedding of CMC and the need to examine jointly antecedents, language acts and consequences.     

The structure of paradigm change

I propose a concise picture of the core structure of paradigm change. It consists of the three basic steps which, I suggest, are common to all forms of paradigm change, individual as well as collective and in every conceptual domain. These steps are formularized so as to stimulate more precise theorizing about, and comparisons between various alleged forms of paradigm change. I explain the idea and give evidence for it using examples from the fields of cognitive psychology, moral psychology, and the history of science.