An example of discovery research involving the transfer of stimulus control

The initial purpose of the present study was to replicate procedures for teaching preschool children to recruit attention at appropriate times by having an experimenter signal the availability and unavailability of attention (i.e., arrange a multiple schedule involving reinforcement and extinction; Tiger & Hanley, 2004). Following the development of discriminated social responding, the schedule-correlated stimuli were removed (i.e., a mixed schedule of reinforcement was arranged). However, discriminated responding continued during these conditions. Further evaluation suggested that stimulus control over children's social responding had transferred from the schedule-correlated stimuli to the delivery of reinforcement. The effect of a history of reinforcement under multiple-schedule conditions on performance under mixed schedules was then replicated with 2 participants in a reversal design. These findings suggest that following experience with schedule-correlated stimuli, these stimuli may be removed with only modest disruption to discriminated responding.     

The scaling of postural adjustments during bimanual load-lifting in traumatic brain-injured adults

Previous postural studies of traumatic brain injury (TBI) patients have been limited to identifying deficits in static and quasi-dynamic postural control tasks such as weight shifting. In this study, we examined whether or not patients with TBI are able to scale adequately their postural adjustments during the performance of the dynamic task of bimanual load-lifting. An age matched group of healthy adults served as controls. We used the Tetrax posturography system that calculates a stability score (ST) based on fluctuations in vertical ground reaction forces, normalized for body weight. During quiet standing, the ST scores of the TBI group were significantly higher than the control group. Forward weight shift and percentage change in the vertical ground reaction forces (lift postural adjustment (LPA) and post-lift postural adjustment (PLPA) scores) linearly increased with increasing load weight in both healthy and TBI subjects. Group differences were found in the magnitude of forward weight shift but not in the relative increase of the LPA and PLPA scores during the lifting and post-lifting phases respectively. The forward weight shift of the TBI group was lower-than-normal and asymmetrical--there was significantly less forward weight shift on the more affected than on the less affected limb. In addition, a significant amplitude coupling was found between the scaling of the weight shift of the heel and forefoot of each limb. However, no coupling was found between the weight shift amplitudes of homologous parts of both limbs in the TBI group. The results showed that scaling based on prior experience was preserved in the TBI group, though some TBI subjects demonstrated absent scaling in either the more affected or less affected heel or forefoot. The differences between the normal and TBI groups in postural adjustments are not necessarily a sign of pathology; rather they may represent a deliberate choice of the central nervous system to counteract predictable disturbances.     

Coping Strategies and Locus of Control as Mediating Variables in the Relation Between Exposure to Political Life Events and Psychological Adjustment in Israeli Children

The relation between political life events and distress was examined with particular emphasis on coping strategies and locus of control as two possible mediators. Subjects were 88 Israeli children. Results partially supported a linear relation between reported impact of exposure and distress. Findings for coping strategies as a mediator suggested, counterintuitively, that greater use of coping strategies is related to more experienced distress. Findings for locus of control as a mediator suggested that subjects with external locus of control experience greater distress, other than in the case of depressive symptomatology. These results indicate that coping strategies and locus of control play a complex role in the stress-outcome relation, the precise nature of which remains to be resolved. Theoretical, clinical and political implications of the findings are discussed.     

The Space of Argumentation: Urban Design, Civic Discourse, and the Dream of the Good City

In this paper, I explore connections between two disciplines not typically linked: argumentation theory and urban design. I first trace historical ties between the art of reasoned discourse and the idea of civic virtue. I next analyze discourse norms implicit in three theories of urban design: Jane Jacobs' The Death and Life of Great American Cities (1961), Christopher Alexander's A Pattern Language: Towns, Buildings, Construction (1977), and Peter Katz's The New Urbanism: Toward an Architecture of Community (1994). I then propose a set of settlement issues of potential interest to both urban designers and argumentation theorists: size, density, heterogeneity, publicity, security, and identity. I conclude by suggesting that the good city be seen as both a spatial and a discursive entity. From such a perspective, good public discourse is dependent, at least in part, on good public space; and good public space is defined, at least in part, as a context conducive to good public discourse.     

Factors which Improve the Construct Validity of Assessment Centers: A Review

This article reviews 21 studies which manipulated specific variables to determine their impact on the construct validity of assessment centers. This review shows that the studies regarding the impact of different observation, evaluation, and integration procedures yielded mixed results. Conversely, dimension factors (number, conceptual distinctiveness, and transparency), assessor factors (type of assessor and type of assessor training), and exercise factors (exercise form and use of role-players) were found to moderate construct validity. On the basis of the review, practical recommendations are derived to maximize the probability that practitioners design and administer an assessment center with construct validity. Finally, new perspectives for future research are identified.     

儿童自我控制学生自陈表的编制

本研究的目的是制定一套测量儿童自我控制能力的自陈式量表,在认知、行为、情绪、社会交往四个主要范畴内编定题目,经过项目分析、因素分析,认为测量儿童自我控制能力的量表包含学习行为、情绪、耐受性和独立性以及生活习惯四个方面的内容,还进一步分析了儿童自我控制的年级差异和性别差异,本量表的信度、效度都较好。     

OVERCOMING AN AUTISTIC CHILD'S FAILURE TO ACQUIRE A TACT REPERTOIRE

A 6-year-old nonvocal autistic girl who had acquired over 30 signs as mands (requests), simple intraverbals (English-sign translations), and imitative responses repeatedly failed to acquire a tact (labeling) repertoire. It was speculated that the verbal stimulus “What is that?” blocked the establishment of stimulus control by nonverbal stimuli. When procedures to transfer stimulus control from verbal to nonverbal stimuli were implemented, the subject quickly learned to tact all 18 target stimuli.     

Optimal sequential designs for on-line item estimation

Replenishing item pools for on-line ability testing requires innovative and efficient data collection designs. By generating localD-optimal designs for selecting individual examinees, and consistently estimating item parameters in the presence of error in the design points, sequential procedures are efficient for on-line item calibration. The estimating error in the on-line ability values is accounted for with an item parameter estimate studied by Stefanski and Carroll. LocallyD-optimaln-point designs are derived using the branch-and-bound algorithm of Welch. In simulations, the overall sequential designs appear to be considerably more efficient than random seeding of items.This report was prepared under the Navy Manpower, Personnel, and Training R&D Program of the Office of the Chief of Naval Research under Contract N00014-87-0696. The authors wish to acknowledge the valuable advice and consultation given by Ronald Armstrong, Charles Davis, Bradford Sympson, Zhaobo Wang, Ing-Long Wu and three anonymous reviewers.     

WILDFLOWERS AND WONDER: A PASTOR'S WANDERINGS IN THE RELIGION-SCIENCE WILDERNESS

Abstract. In this paper, I explore, as a Christian and a parish pastor, what drew me into the religion-science dialogue and what keeps me involved. Encounters with nature and readings of evolutionary theory answer some questions and raise others, especially questions about chance and the nature of God. I persist in my quest for understanding because creedal affirmations of God as Creator demand an examination of the relationship between God and the world, and because I want to proclaim the Christian message in a credible way to parishioners raised with a scientific worldview. Along the way I am reaping unexpected spiritual dividends.     

Establishing appropriate symptomatic control groups for the eating disorders

Two symptomatic control groups for the eating disorders were defined using high and low scores on the Dietary Restraint and Disinhibition scales of the Three Factor Eating Questionnaire. Clinical subjects diagnosed with anorexia and bulimia nervosa were compared with these symptomatic control groups using measures of body weight, bulimic symptoms, and anorexic symptoms. In comparison to the high-Restraint/low-Disinhibition group, anorexic subjects scored higher on measures of eating disorder symptoms but not on Restraint and Disinhibition. The high-Restraint/high-Disinhibition group differed from bulimia nervosa subjects on measures of eating disorder symptoms but did not differ on Restraint and Disinhibition. The results suggested that a control group defined by high Restraint and low Disinhibition formed an appropriate control group for anorexia nervosa. For bulimia nervosa, the most appropriate control group was defined by high Restraint and high Disinhibition.