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21.
Previous studies have shown that the introduction of an interocular delay in presentation to the two eyes of a briefly viewed, haploscopically presented object resulted in a rearward shift in the depth position of this object. The present study investigated the magnitude of this depth shift as a function of flash duration and determined the relationship of this magnitude to two-flash and simultaneity thresholds. It was found that depth shift magnitude decreased as flash duration increased, and that large depth shifts were associated with large two-flash thresholds. The hypothesis that depth shifts can occur within the temporal limits of binocular fusion was supported.  相似文献   
22.
This study was undertaken to examine ambiguities in the ability of the I-E scale to predict complex social behavior. An analysis of the items in the I-E scale suggested that the scale might contain a conservative bias Further, it was suggested that responses to the items may be determined by the individual's political and social ideology, which in turn are influenced by the political and social norms to which he has been exposed The sample consisted of one parent and a college-aged child from 60 upper-middle-class families in which the parent was visible in the community for political and social participation, half the parents interviewed were liberal, and half conservative in their political views A number of measures of political and social participation were administered, along with a shortened version of the I-E scale The findings of the study supported the contention that the “internal” items on the I-E scale are more congenial to persons holding conservative political views than for those holding liberal views. Perceived internal causality, as measured by the I-E scale, was found to be nonsignificantly correlated with any of the measures of political participation for the parent sample, with five of the six correlations being in the opposite direction from that predicted by social learning theory The results of the study were discussed in terms of White's distinction between the “moralizer” and “reformer” approach to social problems The validity of the I-E scale as a measure of a stable personality trait was called into question, as was its usefulness in predicting complex social behavior  相似文献   
23.
A large-sample test for the significance of the difference between two detection data points is developed based upon the assumptions of a one-parameter signal detectability model. In essence, the null hypothesis tested is that two observed data points belong to the samed' function.Portions of this research were supported by Contract DA-49-193-MD-2713 between the University of Washington and the U. S. Army Medical Research and Development Command.Now at Teachers College, Columbia University.  相似文献   
24.
In a booth designed especially for work with both autistic and electively mute children, a 4-yr-old girl named Dolly, who had no communicative speech or imitative skills, was given a preliminary session in which her verbal output was assessed. To elicit sounds from Dolly, an instrument called a “color organ” was used as a positive reinforcer. After this baseline assessment, in 40 half-hour sessions, Dolly was taught to make eye contact with E, and to obey instructions—although it was first necessary to extinguish her disruptive behavior, particularly her opérant crying. In addition, she learned non-verbal imitative behavior, such as hand clapping; and verbal imitative behavior, such as saying “Hi!” Social (play) sessions were begun after session 21, and continued for the remaining time. These were helpful in generalizing Dolly's learned skills to an environment other than the booth; and to other tasks, such as singing “Ee-eye-ee-eye-oh” in the refrain of the song, “Old McDonald”; and pointing to E's eyes, saying “ice”.  相似文献   
25.
Escape behavior under different fixed ratios and shock intensities   总被引:1,自引:1,他引:0       下载免费PDF全文
The effects of ratio length and shock intensity on bar pressing were examined in three rats in two escape-from-shock experiments. In Experiment I, shock intensity was held constant while the schedule was varied from FR 1 to FR 20. The latency of the first escape response increased with FR length while the escape rate, computed as over-all rate in shock minus latency of the first response, decreased at FR 20. In Experiment II, the schedule was held constant at FR 5 while shock intensity was manipulated. Latency decreased as intensity increased, while escape rate increased with intensity, passing through a maximum for two subjects. Responses occurring during the last 100 sec of the 2-min escape period decreased as the FR increased for all subjects, and decreased as shock intensity increased for two subjects.  相似文献   
26.
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   
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28.
The advent of automated assessment contains the seeds of both threat and promise for professional assessors. Placing the problem in the historical and sociological contexts, this article examines computer-based test interpretation (CBTI) and the frequently misunderstood role of actuarial data in relation to it. I argue that sound clinicianship is central not only to the development of adequate CBTI systems, but also to the systems' appropriate and skillful use in practice. When properly utilized by otherwise well-qualified clinicians, CBTI can substantially enhance practice.  相似文献   
29.
Projects importing technology to lesser developed nations may raise five important concerns: famine resulting from substitution of cash crops for subsistence crops, the use of products banned in the United States but permitted overseas, the use of products safe in the U.S. but unsafe under local conditions, ecological consequences of technological change, and cultural disruption caused by displacing traditional ways of life. Are engineers responsible for the foreseeable hunger, environmental degradation, cultural disruption, and illness that results from the project? Are engineers guilty of paternalism if they refuse to accept the project for that reason? Criteria are given to help engineers assess the extent of their responsibility when working in lesser developed nations.  相似文献   
30.
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