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1.
Theories of observing differ in predicting whether or not a signal for absence of reinforcement (S−) is capable of reinforcing observing responses. Experiments in which S− was first removed from and then restored to the procedure have yielded mixed results. The present experiments suggest that failure to control for the direct effect of presenting S− may have been responsible. Pigeons and operant procedures were used. Experiment 1 showed that presentations of S−, even when not contingent on observing, can raise the rate of an observing response that was reinforced only by presentations of a signal (S+) that accompanied a schedule of food delivery. Experiment 2 showed that this effect resulted from bursts of responding that followed offsets of S−. Experiment 3 showed that, when the presence of S− was held constant, lower rates occurred when S− was dependent on, rather than independent of, observing. These results support theories that characterize S− as incapable of reinforcing observing responses.  相似文献   
2.
Jansen (1984) gave explicit formulas for the computation of the second-order derivatives of the elementary symmetric functions. But they are only applicable to those pairs of items which have unequal parameters. It is shown here that for equal parameters similar explicit formulas do exist, too, facilitating the application of the Newton-Raphson procedure to estimate the parameters in the Rasch model and related models according to the conditional maximum likelihood principle.The author wishes to thank the reviewers for their helpful comments on an earlier draft of this paper.  相似文献   
3.
Copthorne Macdonald 《Zygon》1994,29(2):135-151
Abstract. Interpreting the universe as a medium-message process has explanatory value in both scientific and philosophical/spiritual contexts. From this perspective, reality is seen to comprise an enduring medium modulated by transient information. Physically, the medium is energy. Mentally, the medium is awareness. Algorithmically, the medium is an information generator, a programmatic entity that generates temporary informational patterns which modulate the medium's energy aspect in space and time to produce matter and physical phenomena and modulate the medium's awareness aspect to produce subjective experience, mind. In philosophical terms, the medium is Being; the medium modulated by the message is existence.  相似文献   
4.
5.
Assessment and treatment of covert self-injurious behavior are complicated because it is difficult to quantify and apply differential consequences to covert responses. In this study, both tangible and social reinforcers were identified using reinforcer assessment methods. These reinforcers were then provided contingent upon the absence of tissue damage identified during physical examinations, resulting in near 100% success in physical assessment checks that was maintained over 10 months.  相似文献   
6.
In this paper, it is proposed that a) psychosocial medicine is best taught in a setting that provides technical and emotional support, while seizing for teaching only those moments when the learner is most receptive; and b) that the setting should avoid the development of a separate psychosocial skills curriculum, but should take the student where he or she is and integrate the psychosocial skills into his or her everyday biomedical practice. The paper gives specific case examples in which family based psychosocial issues were preeminent in the clinical problem-solving medical residents faced.  相似文献   
7.
Feedback and feedback plus points toward a course grade were applied to the attentional behaviors (defined as the ability to identify the semantic base of text passages) of 30 undergraduate students participating in a reading comprehension development program. Correct underlining was increased, extraneous underlining was decreased, and postreading comprehension test scores improved as a result of the procedures. Scores on a standardized test of reading comprehension also increased significantly.  相似文献   
8.
Some decision analysts recommend reserving their models for careful, complete study of complex problems. Others believe simple problem analyses provide the greatest gains. To clarify these issues, I tested: (1) whether simple published analyses compared to complex ones, produced results as non-intuitive; and (2) whether non-intuitiveness represented analytic gain (or equivalently, intuitive loss). Very limited data also examined (3) the gain from adding model intricacy for a given problem vs. selecting more complex problems for analysis. To assess two non-intuitiveness measures, 75 subjects (33 physicians and 42) non-physicians stated their intuitive preferences in 40 (22 published and 18 unpublished) medical dilemmas. For both physicians and non-physicians, simpler models (those with lees than 30 terminal branches in the decision tree) had about one third the non-intuitiveness of more complex ones. Three tests also supported the premise that analyses outperform intuition, therefore that on average the formers' non-intuitiveness reflects less analytic gain. In addition, for different models of the same problem, tree complexity did not correlate with gain. Thus, simpler trees may not generally gain less because they inadequately describe problems. Instead, simpler analyses may represent simpler problems, with more similar intuitive and formal solutions. If so, these findings may help us avoid some costly but unnecessary simple analyses.  相似文献   
9.
语音信息对不同水平中国英语学习者语义加工的影响   总被引:1,自引:0,他引:1  
研究通过同音异义词对被试判断句子语义正误的干扰实验,来考查语音信息对不同英语水平的中国英语学习者语义加工的影响。实验结果发现,英语水平较高的中国被试所受到的同音异义词的干扰较大,而英语水平普通的被试受到的干扰很小。这一结果说明,英语学习者的水平越高,其语音信息的使用程度越高。  相似文献   
10.
精神医学是临床医学的一个分枝,是高度复杂的一门科学,站在哲学的角度反思,信息系统控制科学方法渗透于精神医学的历史发展过程和临床工作的资料收集、诊断、治疗等各个环节,以及精神医学的科研工作中,还启迪着我国精神卫生事业的发展方向。  相似文献   
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