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911.
The traditional family composition model of children's divorce adjustment was compared to a family competence model. Subjects included 81 children whose parents remained married, were divorced, or were divorced and subsequently remarried. Divorced families had been separated for between 24 and 48 months. Custodial parents completed questionnaires regarding family functioning, occurrence of stressful life events, and child's psychosocial adjustment. Children completed questionnaires regarding parenting behaviors and self-esteem. A trained examiner conducted a structured diagnostic interview of the child. Multivariate analysis of covariance showed that family composition had a significant effect on the occurrence of stressful events and change in income but not children's adjustment. Hierarchical multiple regression correlations indicated the most powerful predictors of child adjustment were family competence variables which accounted for 21% of the variance in child adjustment scores. In contrast, family composition accounted for only 8% of variance in child adjustment scores. Further, hierarchical multiple regression correlations indicated that higher levels of family functioning were associated with families where parental hostility was low and parents displayed few rejecting behaviors while practicing consistent and appropriate discipline.  相似文献   
912.
The development of expert and decision support systems requires the collection, organization, codification, and storage of a body of specialized knowledge. The development, using reconstructive methods, of two such knowledge bases, the first containing the current scientific literature and the second containing an expert’s knowledge, is described for an automated decision support system, the Mental Retardation-Expert. This system provides practitioners with assistance in the treatment of aggressive, self-injurious, and destructive behaviors displayed by individuals with mental retardation or developmental disabilities. The average interobserver reliability of the expert knowledge base ranged from 92.5% to 95.0% when calculated across four clinicians’ assessments of 31 abstracted cases.  相似文献   
913.
This research describes how a currently available spreadsheet program can be set up to analyze sociographic data. An algorithm developed by Jamrich (1960) is presented, along with both the mathematical and the spreadsheet equations. An example of the application of the algorithm and equations to AIDS transmission data is presented.  相似文献   
914.
Checkerboards contain fundamental two-dimensional Fourier components oriented 45° from the edges of individual checks. Previous studies have shown that contingent color aftereffects following adaptation to chromatic checkerboard stimuli were associated with the fundamental components rather than the edges, In the present experiments, we measured contingent color aftereffects, using the method of constant stimuli, after subjects adapted to unfiltered checkerboards and checkerboards with the fundamental Fourier components removed. The adaptation stimuli were magenta (or green) squares and green (or magenta) diamonds; the test stimuli were vertical or oblique sine-wave gratings with different saturations, After adaptation to unfiltered checkerboards, aftereffects contingent on the fundamental components were obtained. In contrast, after adaptation to filtered stimuli, aftereffects of smaller magnitude were found to be aligned with the edges. The data support the previous findings of spatial-frequency-contingent color after-effects with checkerboard adaptation stimuli and indicate that the aftereffects can be associated with edges if the fundamental components of adaptation stimuli are removed by spatial filtering. We reexamined the possibility of color aftereffects induced by imagery of checkerboards. Contrary to the previous reports, no significant aftereffects were obtained.  相似文献   
915.
The Poggendorffillusion has often been explainedas purely an interactionbetween the parallels and the transversals. The present study demonstrates that additional spatial context exerts an influence on this illusion. In Experiment 1, we examined the effects of a surrounding tilted frame (complete and degraded versions) on collinearity adjustments iatheuprightandrotatedPoggendorfffigures. The frame’s orientation was always oblique. Relative to the no-frame condition, frames decreased error in collinearity adjustments in the upright-Poggendorff figure, and increased error in the rotated Poggendorfffigure. In Experiment 2, a circumscribing circle did not cause an orientation-inhibition effect (Ebenholtz & Utrie, 1982, 1983), suggestingthat the effect ofthe frame on the Poggendorif illusion may not be closely related to the rod-and-frame effect. In Experiment 3, orientation of a central texture modulated the magnitude ofthe illusion. The results do not serve to explain the mechanisms behind the Poggendorffillusion, but they do demonstrate the importance of visual reference frames in understanding perceived misalignment.  相似文献   
916.
Sixteen German-English bilinguals were studied in a sleep laboratory for four nonconsecutive nights each. Half were native English speakers living in Zürich, and half native German speakers living in Atlanta. Presleep thought samples were solicited each evening and REM dream reports each night; subjects judged the waking appropriateness of their imagined speech and language phenomena, and also identified waking sources of their dream imagery, the following mornings. Incidences of dreaming and of speech therein generally were similar to those of monolinguals. Whether sessions were conducted in German (two nights) or English (two nights) did directly influence language selection in subjects' dreams. Judged appropriateness of language selection to imagined events was very high for thought samples, and high for REM dreams. Sources for thought samples were generally consonant with the language dominant at study site; for REM dreams this relationship was considerably weaker. Judged waking appropriateness to imagined situations was more strongly related to language selection than was the language reference of the supposed sources of those situations.  相似文献   
917.
918.
An experiment was conducted to examine the contribution of sensory information to asymmetries in manual aiming. Movements were performed in four vision conditions. In the full-vision condition (FV), subjects were afforded vision of both the hand and the target throughout the course of the movement. In the ambient-illumination-off condition (AO), the room lights were extinguished at movement initiation, preventing vision of the moving limb. In the target-off (TO) condition, the target was extinguished upon initiation of the movement. In a no-vision (NV) condition, ambient illumination was removed and the target was extinguished upon initiation of the response movement. Results indicated that accuracy was superior in the full-vision and target-off conditions and when movements were made by the right hand. Movements made by the right hand were also of shorter mean duration. The magnitudes of performance asymmetries were uninfluenced by vision condition. Analyses of movement kinematics revealed that movements made in conditions in which there was vision of the limb exhibited a greater number of discrete modifications of the movement trajectory. On an individual-trial basis, no relationship existed between accuracy and the occurrence of discrete modifications. These data suggest that although vision greatly enhances accuracy, discrete modifications subserved by vision reflect the imposition of nonfunctional zero-order control processes upon continuous higher-order control regimes.  相似文献   
919.
A computational procedure (program) is defined to generate control signals for the motoneuron pools of agonist and antagonist muscles that will move a limb segment from one stationary position to another. The program accounts for the ability to move different distances with different inertial loads and for the influence of instructions concerning movement speed and accuracy. These motor commands allow the program to produce EMG patterns as well as force and kinematic trajectories that are consistent with much of the data found in the literature of these movements. The program is premised on the notion that kinematically defined tasks are accomplished by programming commands to the motoneuron pools, based on only a few cognitively recognized kinematic and dynamic features of the task. Most of the features found in EMG and kinematic patterns can be considered consequences of the program's algorithmic procedures rather than specifically planned features of those movements.  相似文献   
920.
ABSTRACT Subjects consisted of a sample of two cohorts of approximately 100 boys each whose behaviors were rated by their parents and teachers. Criterion variables included antisocial behavior, based on parent, child, teacher, and interviewer reports, and delinquency, based on parent and child reports in addition to cumulative arrest data taken from juvenile court records. The data suggest that mothers are focused on the daily, irritating behaviors of their sons. Teachers, on the other hand, appear to focus on a relatively small number of items (e.g., child physically attacks others, associates with deviant peers), and thereby provide ratings that are better predictors of delinquency and arrest. When the mothers' ratings were constrained to include only items that were salient for teachers, their predictive validity coefficients approached the magnitude of the teacher coefficients.  相似文献   
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