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911.
Delay or rate of food delivery as determiners of response rate   总被引:16,自引:16,他引:0       下载免费PDF全文
Pigeons were confronted with two keys: a green food key and a white changeover key. Food became available for a peck to the green key after variable intervals of time (mean = 113 seconds). A single peck on the changeover key changed the color of the food key to red for a fixed period of time during which the timing of the variable-interval schedule in green was suspended and the switching option eliminated and after which the conditions associated with green were reinstated. In Experiment 1 a single food presentation was obtainable during each red-key period after a minimum delay timed from the switch. This delay and the duration of the red-key period were held constant during a condition but varied between conditions (delay = 2.5, 7.5, 15, or 30 seconds; red-period duration = 30, 60, 120, 240, or 480 seconds). In Experiment 2 additional food presentations were scheduled during a 240-second red-key period with the delay to the first food delivery held constant at 30 seconds, and the delays to later food deliveries varied over conditions. Considering the data from both experiments, the rate of switching to red was a decreasing function of the delay to the first food, the delay to the second food, and perhaps the delay to the third food after a switch. There was no clear evidence that the rate of food in the red-key period made an independent contribution. The ordering of response rates among conditions was consistent with the view that each food presentation after a response adds an incremental effect to the rate of the response and that each food presentation's contribution is a decreasing function of its delay timed from the response.  相似文献   
912.
Especially remarkable seems the rarity of efforts to trace the evolution of the human intellect from that of the lower animals. Since Darwin's discovery, the beasts of the field, the fowl of the air and the fish of the sea have been examined with infinite pains by hundreds of workers in the effort to trace our physical genealogy, and with consummate success; yet few and far between have been the efforts to find the origins of intellect and trace its progress up to human faculty. And none of them has achieved any sure success. (Thorndike, 1911, p. 282)  相似文献   
913.
914.
915.
Various recent works have developed feature or aspect models of similarity and preference. These models are more concerned with the fine detail of the judgment process than were prior models, but nevertheless they have not in general developed an underlying stochastic process compatible with the assumed structure. In this paper, we show that a particular class of multivariate stochastic processes, namely those associated with the Marshall-Olkin multivariate exponential distribution, generates several of these models. In particular, such stochastic processes (appropriately interpreted) yield Tversky's elimination by aspects model, Edgell and Geisler's (normal) additive random aspects model, and Shepard and Arabie's additive cluster model.This work was supported by Natural Science and Engineering Research Council of Canada Grant A8124 to A.A.J. Marley.  相似文献   
916.
It is proved for the common factor model withr common factors that under certain condition s which maintain the distinctiveness of each common factor a given common factor will be determinate if there exists an unlimited number of variables in the model each having an absolute correlation with the factor greater than some arbitrarily small positive quantity.The author is indebted to R. P. McDonald for suggesting the proof of Guttman's determinantal equation for the squared multiple correlation in predicting a factor from the observed variables used in the parenthetical note.  相似文献   
917.
The assumption that the processing stages involved in sentence comprehension are serially and independently executed was tested in two separate experiments using two new sentence types. One experiment was a sentence-picture verification task, the other was not. In Experiment I, subjects viewed sentences such as It's false that the dots are red and indicated, by pressing the appropriate response key, which of two colors would make the sentence true. In Experiment II, subjects verified sentences such as It isn't true that the dots aren't red against pictures of colored dots. On the strength of Sternberg's additive factor method, present findings challenge the validity of the serial, independent stage assumption, and results are alternatively discussed in terms of a capacity sharing model.This research was supported by PHS research grant MH 23401 to Sam Glucksberg, principal investigator.  相似文献   
918.
The intuitionistic consequence operation restricted to the language with (equivalence) and (negation) as the only connectives is axiomatized by means of a finite set of sequential rules of inference.To the memory of Professor Roman Suszko  相似文献   
919.
This paper presents a model for a therapeutic approach to the cultural systems of families. Using anthropologically derived concepts of material and ideational planes of culture, magic, and ritualistic intervention, the inducement of culture change in frozen familial systems is framed in dialectical terms. Four brief case studies are presented describing the systems engaged, the material-ideational rituals employed, and the cultural transformations induced. The paper concludes with a brief discussion of some of the theoretical and practical implications of this cultural approach to the family in therapy.  相似文献   
920.
The relationship between physicians' b]ody movement and judgments of rapport was examined in this study. One-hundred eighteen observers rated physicians' b]ehavior on 14 bipolar scales assessing dimensions of empathy. Physicians' n]onverbal behavior was manipulated so that there were three levels of trunk angle (forward, straight, backward), two levels of arm position (open, folded), two levels of leg position (open, crossed), and two levels of head attitude (nodding, not-nodding). Significant effects were found for trunk angle, head attitude, and arm posture; physicians who leaned forward with open arm positions and nodded their head were judged more positively. Discussion focuses on the reinforcing valuc of nodding, judges' p]erceptions of physicians' a]ccessibility conveyed by trunk and arm postures, and expressions of dominance in physician-patient encounters.  相似文献   
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