Why Do People Engage in Collective Action? Revisiting the Role of Perceived Effectiveness

Research has shown limited support for the notion that perceived effectiveness of collective action is a predictor of intentions to engage in collective action. One reason may be that effectiveness has been in terms of whether the action will influence key decision makers. We argue that the effectiveness of collective action might be judged by other criteria, such as whether it influences third parties, builds an oppositional movement, and expresses values. Two hundred and thirty one attendees at a rally rated the effectiveness of the rally and their intentions to engage in future collective action. For those participants who were not members of an organization, intentions were linked to the perceived effectiveness of the rally in expressing values and influencing the public. For those who were members of an organization, intentions were linked only to the effectiveness of the rally in building an oppositional movement.     

Sample size planning for composite reliability coefficients: accuracy in parameter estimation via narrow confidence intervals

Composite measures play an important role in psychology and related disciplines. Composite measures almost always have error. Correspondingly, it is important to understand the reliability of the scores from any particular composite measure. However, the point estimates of the reliability of composite measures are fallible and thus all such point estimates should be accompanied by a confidence interval. When confidence intervals are wide, there is much uncertainty in the population value of the reliability coefficient. Given the importance of reporting confidence intervals for estimates of reliability, coupled with the undesirability of wide confidence intervals, we develop methods that allow researchers to plan sample size in order to obtain narrow confidence intervals for population reliability coefficients. We first discuss composite reliability coefficients and then provide a discussion on confidence interval formation for the corresponding population value. Using the accuracy in parameter estimation approach, we develop two methods to obtain accurate estimates of reliability by planning sample size. The first method provides a way to plan sample size so that the expected confidence interval width for the population reliability coefficient is sufficiently narrow. The second method ensures that the confidence interval width will be sufficiently narrow with some desired degree of assurance (e.g., 99% assurance that the 95% confidence interval for the population reliability coefficient will be less than W units wide). The effectiveness of our methods was verified with Monte Carlo simulation studies. We demonstrate how to easily implement the methods with easy-to-use and freely available software.     

Is the Web as good as the lab? Comparable performance from Web and lab in cognitive/perceptual experiments

With the increasing sophistication and ubiquity of the Internet, behavioral research is on the cusp of a revolution that will do for population sampling what the computer did for stimulus control and measurement. It remains a common assumption, however, that data from self-selected Web samples must involve a trade-off between participant numbers and data quality. Concerns about data quality are heightened for performance-based cognitive and perceptual measures, particularly those that are timed or that involve complex stimuli. In experiments run with uncompensated, anonymous participants whose motivation for participation is unknown, reduced conscientiousness or lack of focus could produce results that would be difficult to interpret due to decreased overall performance, increased variability of performance, or increased measurement noise. Here, we addressed the question of data quality across a range of cognitive and perceptual tests. For three key performance metrics??mean performance, performance variance, and internal reliability??the results from self-selected Web samples did not differ systematically from those obtained from traditionally recruited and/or lab-tested samples. These findings demonstrate that collecting data from uncompensated, anonymous, unsupervised, self-selected participants need not reduce data quality, even for demanding cognitive and perceptual experiments.     

Generalisation: mechanistic and functional explanations

An overview of mechanistic and functional accounts of stimulus generalisation is given. Mechanistic accounts rely on the process of spreading activation across units representing stimuli. Different models implement the spread in different ways, ranging from diffusion to connectionist networks. A functional account proposed by Shepard analyses the probabilistic structure of the world for invariants. A universal law based on one such invariant claims that under a suitable scaling of the stimulus dimension, generalisation gradients should be approximately exponential in shape. Data from both vertebrates and invertebrates so far uphold Shepard's law. Some data on spatial generalisation in honeybees are presented to illustrate how Shepard's law can be used to determine the metric for combining discrepancies in different stimulus dimensions. The phenomenon of peak shift is discussed. Comments on mechanistic and functional approaches to generalisation are given. Accepted after revision: 10 September 2001 Electronic Publication     

A Deflationist Approach to Indeterminacy and Vagueness

Deflationists cannot make sense ofthe notion of referential indeterminacybecause they deny the existence of substantivereference. One way for them to make sense ofthe objective existence of linguisticindeterminacy is by embracing theworldly (or objectual) view ofindeterminacy, the view that indeterminacyexists not in reference relations but in the(non-linguistic) world itself. On this view,the entire world is divided into precisified worlds, just as it is dividedinto temporal slices and (arguably) alethicpossible worlds. Supervaluationism proves tobe neutral with respect to the debate betweenthe worldly view and the referential view ofindeterminacy.     

Career guidance in England today: reform,accidental injury or attempted murder?

ABSTRACT

In 2011 England's career guidance profession lost its ‘own’ public service organisation and its former dedicated stream of public funding. The immediate causes lay in decisions by the government of the day, but this article revisits the profession's history to seek explanations for its later vulnerability. It is argued that decisions taken early in the profession's history, specifically its complete separation from adult employment services and basing claims to professional expertise almost wholly on occupational psychology, though maybe right at the time, were to have fateful consequences. The article proceeds to argue that career guidance will certainly survive its recent trauma, but the most likely outcome of the current ‘reforms’ – a market in career guidance services – will not create the kind of comprehensive education-to-work bridging service that was once intended and which is still needed.     

Postural Sway and the Amplitude of Horizontal Eye Movements

In 2 experiments, we evaluated relations between postural activity and the amplitude of visually guided eye movements. Participants shifted their gaze to follow horizontal oscillation of a visible target. The target moved with amplitude 9° or 24°. In different experiments, the frequency of target oscillation was 0.5 Hz or 1.1 Hz. In both experiments, the variability of head and torso motion was reduced (in the anterior-posterior axis) when participants viewed moving targets, relative to sway during viewing of stationary targets. Sway variability was not influenced by the amplitude of target motion. The results are compatible with the hypothesis that postural activity was modulated relative to the demands of suprapostural visual tasks.     

Ethical Issues in HIV/STD Prevention Research With High Risk Youth: Providing Help,Preserving Validity

Many preventive intervention studies with adolescents address high-risk behaviors such as drug and alcohol use, and unprotected sex. Randomized controlled trials (RCT) are the gold standard methodology used to test the effectiveness of these behavioral interventions. Interventions outside the rigidly described protocol are prohibited. However, there are ethical challenges to implementing inflexible intervention protocols, especially when the target population is young, experiences many stressful events, and lives in a resource-poor environment. Teens who are at high risk for substance use or sexual risk behaviors tend to be at risk for other problems such as exposure to violence, sexual and physical abuse, depression, and homelessness. How should investigators deal with the psychological and social needs of teenagers in prevention programs in an ethically appropriate way and at the same time preserve the validity of RCT results? We have identified program characteristics, participant characteristics, interaction with parents, and problems with adolescents not in the study as sources of ethical dilemmas in RCT with at-risk adolescents. As a result of our experience, we recommend that every behavioral intervention study develop an ethics protocol, which should include rules for providing help to participants, has contact information for experts to provide guidance, and an emergency procedure for dealing with life threatening situations. In addition, studies should have a resource manual, train research staff in these ethical issues, and work with a data safety and monitoring board or ethics committee.