An Affordance-Based Approach to Visually Guided Overtaking

When an automobile driver overtakes a lead vehicle while avoiding oncoming traffic, does he or she do so with reference to the limits of his or her car? We investigated overtaking from the perspective of the theory of affordances. We define the overtake-ability affordance as a ratio of the minimum satisfying velocity required for safe overtaking (MSV) to the maximum velocity of the driver's car (V_max). Two groups of participants performed overtaking maneuvers, if deemed possible, by driving either a slow (V_max = 25 m/s) or a fast (V_max = 32.5 m/s) virtual car in overtaking situations constrained by 14 values of MSV. For any given MSV condition, participants in the fast car group were more likely to attempt an overtaking maneuver. However, when MSV was expressed in intrinsic units as a ratio of V_max for both groups, the frequency of overtaking was not significantly different across groups. Furthermore, overtaking frequency dropped to near 0% for both groups when MSV exceeded V_max. In accordance with the affordance-based framework (Fajen, 2007), our results suggest that participants select their overtaking maneuvers by perceiving an overtake-ability affordance.     

Religion,Cultural Clash,and Muslim American Attitudes About Politically Motivated Violence

Does adherence to Islam predict attitudes about “suicide bombing” among American Muslims? This study examines the effects of religious and political factors on views of politically motivated violence (PMV). We draw from diverse scholarship, emphasizing arguments that are inspired by Samuel Huntington's Clash of Civilizations perspective, as well as recent work in the sociology of Islam. Using a measure that gauges support for “suicide bombing” from the 2007 Pew Survey of American Muslims, results from logistic regression models suggest that political views and religious factors have a minimal effect on Muslim American attitudes toward suicide bombing. Furthermore, we find that Qur’ānic authoritativeness (i.e., the view that the Qur’ān is the word of God and not written by men) is associated with lower odds of supporting this form of PMV. We discuss the implications of our findings for the often anecdotal and alarmist accounts that link Muslim religiosity to support for “radical” extremism. We close with study limitations and avenues of future research.     

Predictive laws of association in statistics and physics

In the present paper we face the problem of estimating cell probabilities in the case of a two-dimensional contingency table from a predictive point of view. The solution is given by a double stochastic process. The first subprocess, the unobservable one, is supposed to be exchangeable and invariant. For the second subprocess, the observable one, we suppose it is independent conditional on the first one.     

Depression and Suicidal Ideation After Predictive Testing for Huntington's Disease: A Two-Year Follow-up Study

The present study reports a two-year follow-up of psychological effects of predictive testing for Huntington's disease. Questionnaires assessing depression, general health, well-being, self injurious behavior, life satisfaction, and lifestyle were completed by 35 carriers and 58 non-carriers before the predictive test, and 2, 6, 12, and 24 months afterwards. Both carriers and non-carriers showed high suicidal ideation before the predictive testing. Depression scores and frequency of suicidal thoughts increased for carriers, compared to non-carriers, over time. There were no differences regarding life satisfaction or life style between carriers and non-carriers. Predictive testing was beneficial in reducing overall ill-health symptoms and increasing well-being for those initially expressing concern about Huntington's disease. The importance of assessing suicidal ideation and of continuing to provide adequate support is emphasized.     

The psychology of engagement with indigenous identities: a cultural perspective

In a questionnaire study among 124 students at Haskell Indian Nations University, the authors investigated the hypothesis that engagement with Indigenous identity--assessed along three dimensions including degree (identification scale), content (panethnic or tribal nation), and context (reservation or nonreservation)--can serve as a psychological resource for well-being and liberation from oppression. Consistent with this hypothesis, degree of identification was positively correlated with community efficacy and perception of racism. Apparently inconsistent with this hypothesis, degree of identification among students who had resided on a reservation was negatively correlated with the Social Self-Esteem subscale of the Current Thoughts Scale. Rather than evidence against the identity-as-resource hypothesis, this pattern may reflect the cultural grounding of self-esteem and tools designed to measure it.     

Concreteness and item-to-list context associations in the free recall of items differing in context variability

Context variability can be defined as the number of preexperimental contexts in which a given concept appears. Following M. Steyvers and K. J. Malmberg's (2003) work, the authors have shown that concepts that are experienced in fewer preexperimental contexts generally are better remembered in episodic memory tasks than concepts that are experienced in a greater number of preexperimental contexts. The purpose of this article is to demonstrate that low context variability confers its memorial advantage because of stronger item-to-list context associations as compared with high context variability. Three experiments that use environmental context changes from study to test demonstrate that the low context variability advantage is eliminated when item-to-list context associations are not available because of environmental changes at test. In addition, the low context variability advantage is eliminated when inward processing at study prevents the formation of item-to-list context associations.