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51.
Six pigeons were trained with a chain variable-interval variable-interval schedule on the left key and with reinforcers available on the right key on a single variable-interval schedule arranged concurrently with both links of the chain. All three schedules were separately and systematically varied over a wide range of mean intervals. During these manipulations, the obtained reinforcer rates on constant arranged schedules also frequently changed systematically. Increasing reinforcer rates in Link 2 of the chain increased response rates in both links and decreased response rates in the variable-interval schedule concurrently available with Link 2. Increasing Link-1 reinforcer rates increased Link-1 response rates and decreased Link-2 response rates. Increasing reinforcer rates on the right-key schedule decreased response rates in Link 1 of the chain but did not affect the rate in Link 2. The results extend and amplify previous analyses of chain-schedule performance and help define the effects that a quantitative model must describe. However, the complexity of the results, and the fact that constant arranged reinforcer schedules did not necessarily lead to constant obtained reinforcer rates, precluded a quantitative analysis. 相似文献
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Pigeons were trained under a discrete-trials detection procedure in which one of a set of color stimuli was presented on the center key and a single response turned off the stimulus and illuminated two side keys. Single responses to one or the other side key produced occasional reinforcers depending on the value of the color stimulus. In Experiment 1, one color-stimulus set comprised 559, 564, 569, and 574 nm, and right-key pecks were occasionally reinforced following presentations of members of this set. The other stimulus set comprised 579, 584, 589, and 594 nm, and left-key pecks were occasionally reinforced following presentations of members of this set. Across seven experimental conditions, the left/(left + right) relative reinforcer frequency was varied from .1 to .9. In Experiment 2, one stimulus set contained only one member, 574 nm, and right-key responses were occasionally reinforced following its presentation. Over 12 experimental conditions, two manipulations were carried out. First, the number of stimuli comprising the other stimulus set was increased from one (579 nm) to two (579 and 584 nm) to three (579, 584, and 589 nm) and to four (579, 584, 589, and 594 nm), and left-key responses were reinforced occasionally following center-key presentations of members of this set. Second, for each stimulus combination, the left/(left + right) relative reinforcer frequency was varied from .1 to .5 to .9 across three experimental conditions. The principal finding of Experiments 1 and 2 was that reinforcers and stimuli interacted in their effects on behavior. In Experiment 3, pairs of adjacent stimuli (5 nm apart) in the range 559 to 594 nm were presented in each experimental condition, and the left/(left + right) relative reinforcer frequency was held constant at .5. The data from all three experiments were analyzed according to a detection model describing performance in multiple-stimulus two-response procedures. This model provided independent measures of stimulus discriminability, contingency discriminability, and bias. The analysis showed that (a) consistent with the color-naming function, pigeons were better able to discriminate between higher nanometer values than lower nanometer values; (b) their ability to discriminate between the stimuli was independent of the number of wavelengths comprising each stimulus set; (c) they allocated delivered reinforcers very accurately to the previously emitted response; and (d) no consistent biases emerged. 相似文献
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一、从1966到1976年,是解释学尤其是“哲学解释学”内部急剧发展的十年,是它同当代各种思想流派对话、进行活跃的“解释的论战”的十年。我们可以用P.利科尔在《论解释》一书(1965)中的一句话,即“语言的问题和原文(或译为本文——译者)解释的问题已经变为当代思想的十字路口”,来说明这整个十年的情况。除了传统的解释学、神学的解释学和H.-G.加达默尔的哲学解释学以外,其他思想运动也一一涌现了出来——例如结构主义、符号学、拉康的以语言为中心的弗洛伊德精神分析学、福柯以及对尼采的研究。后面这些研究的发展使国际上认为法国在语言理论和原文解释理论方面是大步前进的研究中心。当然,有 相似文献
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在当代思想斗争中,下述的问题也具有重要的意义,即:对传统所理解的逻辑问题的创造性探讨,马克思是否起过重大促进作用?人们都很清楚,马克思常常被承认为伟大的政治经济学家,但同时却否定他在探讨逻辑问题上的任何作用。在资产阶级思想家中间不时地传来这样的声音:马克思的唯物辩证法至多不过是关于历史的学说,是与逻辑、“演绎意义的逻辑”理论毫无关系的、单纯的经验-描述理论。例如,鲍波尔说:“因为可以把逻辑看作为演绎理论。但是我们没有任何根据假定,辩证法与演绎有某 相似文献
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“唯物主义”一词含义模糊:它既指一种道德学说,又指一种哲学,并且确实指一种完整的世界观。道德唯物主义相当于快乐主义,或相当于那种让人们仅仅追求自身快乐的学说。哲学唯物主义认为,实在的世界完全是由物质的东西构成的。从逻 相似文献
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我们认为以活动为中心的初中理科班是对两个种族组行为进行比较、对照的理想研究。理由是这些班的学生可以相对自由地选择自己的座位,可以选择伙伴做实验项目,还可以自由支配使用自己的时间。从这些行为中,我们能够对取消了种族隔离的学校中种族间关系的性质,以及对每个五文化组学习科学动机的程度作出推论。此外,也可能确定课堂行为与教师评分之间的关系。在此类班级中成绩的评定,依据的是作业或学习项目的进步,项目结束后的测验、平时测验、最后测验以及教师对学生努力程度的估计。因此,本研究意在回答下列问题: 1.在种族平等以活动为中心的初中理科班中,黑人和自人男生是怎样上课的?行为上 相似文献
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