The counterintuitive impact of responses and response times on parameter estimates in the drift diffusion model

Given a drift diffusion model with unknown drift and boundary parameters, we analyse the behaviour of maximum likelihood estimates with respect to changes of responses and response times. It is shown analytically that a single fast response time can dominate the estimation in that no matter how many correct answers a test taker provides, the estimate of the drift (ability) parameter decreases to zero. In addition, it is shown that although higher drift rates imply shorter response times, the reverse implication does not hold for the estimates: shorter response times can decrease the drift rate estimate. In the light of these analytical results, we illustrate the actual impact of the findings in a small simulation for a mental rotation test. The method of analysis outlined is applicable to a broader range of models, and we emphasize the need to further check currently used reaction time models within this framework.     

Textured Foot Orthotics on Dynamic Stability and Turning Performance in Parkinson’s Disease

Abstract

The purpose of this study was to facilitate sensory feedback, with textured foot orthotics, to evaluate dynamic stability and turning behavior in Parkinson’s disease individuals. Seven participants with a diagnosis of idiopathic Parkinson’s disease, aged 55–80?years old, participated in this study. Participants completed three testing sessions; baseline, 4?weeks post-baseline, and 5?weeks post-baseline. Three experimental conditions were tested: footwear only (F), footwear?+?non-textured orthotic (FO), and footwear?+?textured orthotic (FOT). Kinematic, kinetic, and video data were collected during the steps preceding a turn task. Variables of interest included dynamic stability (maximum mediolateral (ML), minimum ML, and ML range of the center of mass (COM)-base of support (BOS) relationship) and turning performance (gait velocity and step count). There was a statistically significant increase in maximum ML COM-BOS distance (week 4 [0.1298 m?±?0.054] compared to week 0 [0.1069 m?±?0.050] p = .0076), and a significant decrease in step count (week 0-F [5.52 steps ± 1.08] to week 0-FO [5.23 steps ± 0.87] p = .0296) and (week 4-FO [5.24 steps ± 1.31] to week 4–FOT [4.67 steps ± 0.76] p = .0004). Textured foot orthotics modified dynamic stability and turning performance in Parkinson’s disease individuals completing a 180° degree turn. These preliminary results support this potential treatment option for rehabilitation professionals treating Parkinson’s disease.     

Reliability in Dream Research: A Methodological Note

The coefficients of internal consistency and retest reliability had been rarely investigated within the methodology of dream content analysis. Analyzing a dream series of elderly, healthy persons obtained from weekly telephone interviews, the internal consistency of a series of 20 dreams and retests after 4 or 22 weeks, respectively, had been computed. The findings indicate that dream recall and dream length are quite stable, but dream characteristics such as bizarreness and emotional tone underlie large intraindividual fluctuations. In order to obtain reliable measures for these variables which will be important for correlational studies, including waking-life trait measures, one has to obtain as many dreams as possible (about 20) in a very short time period. Further research is needed to extend the present findings to diary dreams and laboratory dreams.     

Reimagining Just War as Anchored in,Tethered to,and Tempered by Mercy

This essay considers whether the just war tradition is compatible with Christian theologically grounded conceptions of mercy. After considering and rejecting positions that pit mercy and war against each other, the essay mines the work of Walter Kasper and James Keenan on Christian mercy to develop a position that reimagines mercy as compatible with traditional just war criteria. In particular, this analysis leads to the conclusion that Christians may endorse just war in the form of humanitarian intervention. By doing so, they allow mercy to temper the aspects of warfare that diminish the humanity of others.     

Why do new members stop attending health and fitness venues? The importance of developing frequent and stable attendance behaviour

ObjectivesAttendance at health and fitness venues often declines dramatically during the first year of membership. The present study sought to identify factors associated with continued attendance in new members.MethodsA secondary data analysis was conducted on the attendance data of 1726 new members of a health and fitness organisation over the first 12 months of their membership. Associations were assessed between members’ frequency and pattern of attendance during the first quarter of their membership, age, gender, and home location and their attendance levels in the fourth quarter after joining.ResultsThere was a significant reduction in the frequency of attendance over time from a mean of 7.48 times in the first month to a mean of 0.92 in the 12th month after joining. Older age, starting membership in the autumn or spring, frequency of attendance in the first quarter and stability of the context of attendance (i.e., same time and location) in month three were all significantly associated with increased attendance levels in the fourth quarter.ConclusionsThe findings indicate that new members’ early attendance behaviour, in terms of the frequency and the stability of attendance, may be important for supporting continued attendance at health and fitness venues. Interventions to increase longer-term attendance and, in turn, physical activity, should focus on promoting regular and consistent attendance, especially in terms of day, time and location, early on in individuals’ membership of health and fitness venues.     

Shedding light on the relationships between Machiavellianism,career ambition,and unethical behavior intention

ABSTRACT

This research aims at revealing how Machiavellianism correlates with the propensity to engage in unethical behavior. The mediating role of career ambition was thus investigated for this purpose. This research posits that career ambition partially mediates the relationship between Machiavellianism and unethical behavior intention. The research model was tested via Structural Equation Modeling (SEM). Research data were collected from full-time hotel employees and managers in Antalya, Turkey. The findings revealed that Machiavellianism positively correlated with career ambition and unethical behavior intention. Furthermore, the mediating role of career ambition in the relationship between Machiavellianism and unethical behavior intention was verified. Specifically, Machiavellianism predicted career ambition, which in turn predicted unethical behavior intention. Finally, considering the fact that the dark sides of the antecedents and consequences of career ambition have been neglected to a significant extent in the literature, the current study makes a significant contribution to filling this gap.     

Stability and change of basic personal values in early adulthood: An 8-year longitudinal study

We examined four types of stability and change in values during young adulthood. 270 respondents (aged 20–28, 54% female) completed the Portrait Values Questionnaire at three time points, separated by 4 years. Rank-order stability coefficients of the 10 values averaged 0.69 (T1-T2) and 0.77 (T2-T3). The mean importance of conservation, self-transcendence, and power values increased over time, the mean importance of achievement values decreased, and openness to change values remained stable. For 75% of respondents, the correlations of the within-person value hierarchies exceeded 0.45 from T1 to T2 and 0.61 from T2 to T3. Correlations among individual change scores for the 10 values formed coherent patterns of value change that mirror the circular structure of Schwartz’s theory.     

Postural Stability in Children with High Sacral Level Spina Bifida: Deviations from a Control Group

Abstract

Objective: To assess static and dynamic postural stability changes in children with high sacral level spina bifida.

Methods: Thirty-five children with high sacral level spina bifida and 35 age-matched healthy controls were enrolled. Their lower extremity muscle strengths and static and dynamic postural stability parameters were measured with the use of a dynamometer and the NeuroCom Balance Master^® device, respectively. Functional gait and balance were evaluated using the five times sit-to-stand test (5STS) and the 6-minute walk test (6MWT). Spinal, hip, and ankle deformities of the patient group were measured by radiologic evaluation.

Results: In comparison with controls, patients were found to have lower ankle dorsiflexion and plantar-flexion strength, increased 5STS duration, and decreased 6MWT distance while both static and dynamic postural stability parameters were significantly different. Bilateral ankle muscle strengths were found to be negatively correlated with postural stability parameters. The presence of hydrocephalus or meningomyelocele in the patient group was found to have negative effects on static postural stability.

Conclusion: Static and dynamic postural stability is affected even in children with high sacral level spina bifida who are expected to have best condition in this patient population. The ankle muscle strength is the main factor influencing these changes.