Assessing bimodality to detect the presence of a dual cognitive process

Researchers have long sought to distinguish between single-process and dual-process cognitive phenomena, using responses such as reaction times and, more recently, hand movements. Analysis of a response distribution’s modality has been crucial in detecting the presence of dual processes, because they tend to introduce bimodal features. Rarely, however, have bimodality measures been systematically evaluated. We carried out tests of readily available bimodality measures that any researcher may easily employ: the bimodality coefficient (BC), Hartigan’s dip statistic (HDS), and the difference in Akaike’s information criterion between one-component and two-component distribution models (AIC_diff). We simulated distributions containing two response populations and examined the influences of (1) the distances between populations, (2) proportions of responses, (3) the amount of positive skew present, and (4) sample size. Distance always had a stronger effect than did proportion, and the effects of proportion greatly differed across the measures. Skew biased the measures by increasing bimodality detection, in some cases leading to anomalous interactive effects. BC and HDS were generally convergent, but a number of important discrepancies were found. AIC_diff was extremely sensitive to bimodality and identified nearly all distributions as bimodal. However, all measures served to detect the presence of bimodality in comparison to unimodal simulations. We provide a validation with experimental data, discuss methodological and theoretical implications, and make recommendations regarding the choice of analysis.     

Breaking Down Barriers: Museum as Broker of Home/School Collaboration

ABSTRACT

Parents have a major influence on children's learning, yet parent involvement remains weak in many communities. This article addresses the role of a museum in bringing home and school together, describing results from 2 complementary studies of a museum-designed and -implemented parent involvement program. The first study was an exploratory, mixed-methods investigation designed to understand the program's impact on parents' engagement in their children's learning. The second study used a grounded theory approach to develop theoretical hypotheses about the programmatic mechanisms that facilitated parents' engagement. In terms of impact, the program gave parents a platform through which to create new and more meaningful spaces for connecting to their children's learning, including conceptual spaces, social spaces, and physical spaces. In terms of mechanisms, the program first helped parents to build relevant capital and then to author new and relevant ways of engaging with their children's schooling. Taken together, study results broaden current thinking about the spaces in which parent engagement occurs and emphasize the important community-based role that museums can play to bring parents and schools together in support of children's development.     

Religion and spirituality in the context of bipolar disorder: a literature review

Religion and spirituality (R/S) may play an important role for individuals with bipolar disorder (BD) by providing a means of coping with, and an explanatory model for, their disorder. We conducted a systematic review of empirical studies that have explored R/S in individuals with BD or samples that explicitly delineate individuals with BD. Only six studies met our inclusion criteria. Findings from these studies suggest that R/S strategies may be important for some people in the management of BD. Religion and spirituality thus become relevant concerns for a therapeutic regime that seeks to develop wellness within a bio-psycho-social model. However, the limited body of research and methodological shortcomings of existing research make it difficult to draw relevant conclusions about how this might be accomplished. The authors propose a need for longitudinal, prospective, mixed methods research in order to inform evidence-based practice.     

Inspection Times and the Selection Task: Are They Relevant?

Five experiments are reported based upon Evans' (1996) inspection time paradigm in which subjects are required to solve computer-presented Wason Selection Task problems while simultaneously using a mouse to indicate which card is currently under consideration. It had previously been found that selected cards were inspected for considerably longer than were non-selected cards, and this was taken as support for the existence of pre-conscious heuristics that direct attention towards relevant aspects of a problem. The first experiment reported here fully replicated this effect. However, by systematically varying the task format in subsequent experiments, the effect was found to diminish, disappear, or even reverse. The change in effect size and direction was not accompanied by any systematic variations in the subjects' card choices, indicating that the changes in taskformat had not altered the operation of the relevance-determining heuristics. On balance, it is suggested that the inspection time effect appears to be artefactual, and the inspection time paradigm therefore does not constitute satisfactory evidence for the existence of pre-conscious heuristics.     

From Modal Discourse to Possible Worlds

The possible-worlds semantics for modality says that a sentence is possibly true if it is true in some possible world. Given classical prepositional logic, one can easily prove that every consistent set of propositions can be embedded in a ‘maximal consistent set’, which in a sense represents a possible world. However the construction depends on the fact that standard modal logics are finitary, and it seems false that an infinite collection of sets of sentences each finite subset of which is intuitively ‘possible’ in natural language has the property that the whole set is possible. The argument of the paper is that the principles needed to shew that natural language possibility sentences involve quantification over worlds are analogous to those used in infinitary modal logic.     

Knowledge to Wisdom: We Need a Revolution

Introduction The following document is a very brief summary of a thesis and argument that I have devoted the last 30 years of my life to trying to get across to my fellow human beings. It was first spelled out in What’s Wrong With Science? (Bran’s Head Books, 1976) and subsequently in From Knowledge to Wisdom (Blackwell, 1984), Is Science Neurotic? (Imperial College Press, 2004) and numerous articles, references to which can be found on . Three years ago an international group was formed, called Friends of Wisdom, which seeks to get across to academics and the public the compelling arguments and urgent need to transform academic inquiry so that its basic aim becomes to seek and promote wisdom. The document below is taken from the website of Friends of Wisdom, the URL of which is . It is the mission statement of Friends of Wisdom. You are invited to join.