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91.
A comparative analysis was conducted of five different methods for scoring the Rod-and-Frame Test to examine the convergent validities of each of the five methods with performance on the Embedded Figures Test for a sample of 408 13- to 16-yr.-olds. The scoring methods included the absolute error, the algebraic error, the absolute value of the algebraic error, the frame effect, and an assessment of relative field dependence. Correlations obtained among the five methods and the Embedded Figures Test indicated different patterns for boys and girls. In general, the method which employed the absolute value of the algebraic error yielded the strongest convergent validity coefficients with scores on the Embedded Figures Test and Group Embedded Figures Test for boys (.62 and -.54, respectively), although, for girls, the absolute algebraic error and absolute error both yielded coefficients of .50 with Embedded Figures Test scores and -.46 with Group Embedded Figures Test scores.  相似文献   
92.
Séré B  Marendaz C  Hérault J 《Perception》2000,29(12):1403-1412
The aim of this research is to model and simulate the loss of visual resolution as a function of retinal eccentricity in the perception of natural scenes. The model of visual resolution is based on a space-variant low-pass filter, having a variable convolution kernel according to retinal eccentricity. The parameters of the model are computed from psychophysical measures of visual acuity as a function of retinal eccentricity. The implementation of the model allowed us to generate images of scenes with nonhomogeneous space-variant resolution, simulating the filtering executed by the eye. These scenes are used to test and optimise the model by means of experiments in static vision (through tachistoscopic presentations) and in dynamic vision where the resolution of the scene is computed, in real-time, as a function of the location of gaze.  相似文献   
93.
In search of remembrance: evidence for memory in visual search   总被引:2,自引:0,他引:2  
Observers searched for a target among distractors while the display items traded places every 110 ms. Search was slower when the target was always relocated to a position previously occupied by a distractor than when the items remained in place, showing the importance of memory for locations in a visual search task. Experiment 2 repeated a previous study in which items could move to any location within the display, but used a larger range of set sizes than tested in the earlier study. A cost in search times to relocating items was found at the larger set sizes, most likely reflecting that the probability that the target would replace a distractor increased witht he set size. The findings provide strong evidence for the role of memory for locations within trials in a visual search task.  相似文献   
94.
The purpose of this study was to identify factors associated with early onset of sexual intercourse. Within an ecological system's conceptual framework, familial factors associated with early onset of sexual activity were identified in a sample of 425 adolescents from San Juan metro area schools. Measures included questions about sexual activity, sexual permissiveness, and such familial variables as: discipline, parental supervision, and parental support. Significant relationships were observed between early onset of sexual intercourse and parental supervision, discipline, parental support, and parents' marital status. Results suggest the key role of parents and family in prevention of HIV-risk behaviors among adolescents in terms of delaying sexual onset. Overall, the study described youths who postponed sexual activity as having greater support, supervision, and parental involvement.  相似文献   
95.
The structure of goal contents across 15 cultures   总被引:4,自引:0,他引:4  
The authors investigated the structure of goal contents in a group of 1,854 undergraduates from 15 cultures around the world. Results suggested that the 11 types of goals the authors assessed were consistently organized in a circumplex fashion across the 15 cultures. The circumplex was well described by positioning 2 primary dimensions underlying the goals: intrinsic (e.g., self-acceptance, affiliation) versus extrinsic (e.g., financial success, image) and self-transcendent (e.g., spirituality) versus physical (e.g., hedonism). The circumplex model of goal contents was also quite similar in both wealthier and poorer nations, although there were some slight cross-cultural variations. The relevance of these results for several theories of motivation and personality are discussed.  相似文献   
96.
On March 11, 2004, Al-Qaeda set off 10 bombs on several train routes in Madrid. 192 people were killed and 2,000 wounded. In this study, 1,179 questionnaires were administered Week 2 after the attacks to residents 18 years and over from the affected geographical areas. The questionnaire included items about sociodemographic variables and exposure to the attacks. Psychological effects were assessed as presence of acute stress and depressive symptomatology and functional impairment. 46.7% of the sample presented symptomatology of acute stress and 49.6% depressive symptoms. Among the symptoms of acute stress, the most frequent were re-experiencing (72.5%) and dissociative symptoms (71.8%). The chief predicting variables in symptomatology were being female, over 65 yr. old, and a habitual train user. The large number of affected people was refined with an item analysis and the consideration of severity of interference in psychosocial functioning.  相似文献   
97.
This study examined the dimensional structure of Tomás-Sábado and Gómez-Benito's Death Anxiety Inventory and Templer, et al.'s Death Depression Scale-Revised. The responses of 244 Spanish nurses to the Spanish forms of both scales were evaluated by means of a principal axis factor analysis with direct Oblimin rotation. Five significant factors were identified: Internally Generated Death Anxiety, Death Depression, Externally Generated Death Anxiety, Death Threat, and Death Sadness, accounting for 51.6% of the variance. The distribution of the factor loadings for the items of both scales on the five factors supported the discriminant validity of the constructs specific to each of the scales and justified their use in evaluating death anxiety and death depression independently.  相似文献   
98.
In this paper we present the syntax and semantics of a temporal action language named Alan, which was designed to model interactive multimedia presentations where the Markov property does not always hold. In general, Alan allows the specification of systems where the future state of the world depends not only on the current state, but also on the past states of the world. To the best of our knowledge, Alan is the first action language which incorporates causality with temporal formulas. In the process of defining the effect of actions we define the closure with respect to a path rather than to a state, and show that the non-Markovian model is an extension of the traditional Markovian model. Finally, we establish relationship between theories of Alan and logic programs.  相似文献   
99.
100.
The purpose of this paper is to examine the effectiveness of Reconnecting Youth, a prevention program for at-risk high school youth. Data are from a large, independently evaluated effectiveness trial in two diverse urban school districts. A total of 1,218 students participated; 50% were male; average age was 15. We tested whether positive efficacy trial effects could be replicated, and whether any negative behavioral effects occur when clustering high-risk youth. Although mixed program effects were observed at immediate post-intervention, only negative effects were found at 6-month follow-up. These effects included less optimal scores on measures of GPA, Anger, School Connectedness, Conventional Peer Bonding, and Peer High-Risk Behaviors. Overall, we found little support for the use of this social-influence—model intervention aimed at increasing school connectedness for high-risk youth. Further, this study provides evidence that clustering high-risk youth in preventive interventions has the potential for iatrogenic effects.  相似文献   
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