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131.
Pigeons' responses were reinforced on two identical and concurrently available chain variable-interval-schedules. Unlike the typical concurrent chains procedure, both links were operative throughout, thus producing three types of concurrency: (1) concurrent initial links; (2) concurrent initial and terminal links; (3) concurrent terminal links. Choice proportions in each of these three states suggested that the pigeons were sensitive to momentary likelihoods of reinforcement: choice proportions for a schedule were higher when the schedule had been operative for some time, resulting in a higher probability of reinforcement. The study also showed that the relative rates of responding did not match the relative rates of reinforcement in any of the three states of concurrency. Instead, the choice proportions in both the concurrent initial and in the concurrent terminal links were intermediate between the scheduled and the obtained relative rates of reinforcement, while the choice proportions for a terminal link concurrent with an initial link consistently overmatched the relative interreinforcement times (and were typically 1.00). These data indicate that an accurate characterization of choice may not be obtained by considering only the relative interreinforcement interval where one interreinforcement interval is segmented into a chain. Instead, the organism's choice for a schedule will be substantially lowered by the chaining operation. 相似文献
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Pigeons' responses in the presence of two concurrently available (initial-link) stimuli produced one of two different (terminal-link) stimuli according to identical but independent variable-interval schedules. Responding in the mutually exclusive terminal links was reinforced with food according to fixed-ratio schedules for six pigeons and according to fixed-interval schedules for two pigeons. None of the pigeons matched the proportion of (choice) responses in the initial links to the proportion of the rates of reinforcement obtained during the terminal links. Instead, as the values of each of the terminal-link schedules were increased by a constant amount, the choice proportions for the stimulus associated with the smaller of the two values increased, even though the relative rates of reinforcement during the terminal links decreased. These results are incompatible with those from previous studies with aperiodic (variable-interval or variable-ratio) schedules. The present results do suggest, however, that in transforming aperiodic schedules into their periodic equivalents, it may be necessary to consider the size of the smallest interreinforcement interval comprising the terminal-link schedules. 相似文献
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Pigeons had been trained to peck a key when each peck removed a slowly increasing series of electric shocks. Without loss of the established key-pecking response, the birds were gradually weaned from this procedure to one where intense shocks were presented suddenly, duplicating features that had proved ineffective for initial shaping of the response. Finally, a procedure was introduced in which key pecks could avoid shock. Avoidance responding was maintained in two of three pigeons. 相似文献
136.
卡达穆尔的《真实性和方法》一书是用以论证一种“哲学诠释学”的,它的第一部分在方法论上是其他一切部分的基础,涉及审美尺度的超验问题,并在这个基础上设想出一种艺术作品的本体论。如果我们要对这部广博的、内容丰富的著作加以批判,我们首先就必须讨论它的第一部分。 相似文献
137.
近来在印度学家中间,从马克思主义立场来深入研究印度哲学的历史开始获得愈来愈大的威望。虽然在这一方面马克思主义者刚刚走上开始的阶段,他们却巳写出了一系列印度哲学史的重要著作,其中包括Д.П.恰托帕驮耶的这本著作。还在1956年,该书首次以印地文出版;但是对本书的兴趣如此之大,以致于1959年出版了它的英译本,1961年出版了从英译本转译的俄译本。恰托帕驮耶的这本书无疑是从马克思主义立场研究印度哲学某些根本问题的较有份量的著作之一。作者用了大量的实际材料,其中大部分以往从未进行过科学的整理。该书不仅探讨了古代 相似文献
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在马克思主义认识论中,感性的经验或感性经验这一概念是作为认识的第一阶段的标志使用的。但是,以感觉、知觉、表象为形态所引出的对物质现实性的具体直观的映象的感性经验,还没有表达出人类经验的全部和实质。如果谈到共产党和工人党在为了民主和社会主义反对剥削和压迫、反对帝国主义和战争的革命斗争过程中所取得的经验时,这就非常清楚了。显然这里所指的不单是感性经验形态的经验,而是从革命实践中所取得的、具有判断性质的概括形式的认识。如果人们进一步观察在社会主义社会中具有多种多样形式并且是社会主义生产关系的一种表现的经验交流时,那就可证明,感性 相似文献