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Houston A 《Journal of the experimental analysis of behavior》1986,45(1):15-18
Field data concerning the time budgets and foraging success of pied wagtails (Motacilla alba yarrelli, Gould) are reanalyzed. It is found that the data are well described by the generalized matching law, with a marked bias towards spending time on the territory. In this case matching is not the result of maximizing reward rate, but it remains possible that it results from an allocation of time that maximizes survival. 相似文献
124.
Three experiments describe the effects of manipulating the frequency of response-reinforcer contiguity in a recycling conjunctive schedule. The schedule arranged that a reinforcer was delivered after 30 s provided at least one response had occurred; otherwise the next cycle started immediately. In Experiment 1, this schedule produced the typical pause–respond–pause pattern, with most responses at mid-interval; and, when a limited number of contiguities between responses and food delivery were added, the pattern became more like the monotonic scallop seen on fixed-interval schedules. In Experiment 2, the schedule was initially presented with an additional contingency that allowed contiguity on every trial. Fixed-interval-like behavior occurred and tended to persist as contiguities were gradually eliminated. In Experiment 3, the recycling conjunctive schedule alternated with a condition in which a large number of contiguities occurred. The pause–respond–pause pattern and fixed-interval-like performance occurred with few or many contiguities, respectively. The results of all three experiments illustrate how contiguity interacts with a small number of other variables to determine performance on interval schedules and illuminate previous findings with fixed-interval and fixed-time schedules. 相似文献
125.
Ferrandez A 《Journal of motor behavior》1986,18(4):475-485
The aim of this study was to investigate the modulations of locomotion induced by a rhythmic cognitive task (counting one's steps). Subjects (6- and 8-year-olds and adults) were requested to walk freely, and then to walk while counting their steps. Here a decrease in cadence values was observed in children only, with quasi-total repercussions on velocity at the age of 6 only. The spatiotemporal structuring of locomotion described here is already present at 6 years of age and is not altered in the step-counting situation: strong links were observed between cadence and velocity, and between stride length and velocity, and weak links between cadence and stride length. 相似文献
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Lavin M 《Journal of applied philosophy》1986,3(1):89-101
ABSTRACT 'Ulysses contracts' are an instrument through which a psychiatric patient may prearrange involuntary commitments to be put into effect if the patient satisfies certain diagnostic criteria in the future. Proposals for Ulysses contracts typically impose numerous safeguards. This paper argues against the intuitively plausible safeguard which permits only presently remitted patients to contract. Instead of requiring a patient's remission, it is argued that the appropriate safeguard is the patient's ability, whether remitted or not, to offer good reasons for wishing to contract. In short, what matters is not an executive's character, but an executive's reasons, and a bad executive may have good reasons. Attempts to deny the accessibility of good reasons in unremitted patients are rejected on the ground that psychiatric diagnosis requires psychiatrists to be able to distinguish between good and bad reasons in both remitted and unremitted patients. If psychiatrists cannot do that, psychiatric diagnosis is impossible. 相似文献
128.
Donchin A 《希帕蒂亚:女权主义哲学杂志》1986,1(2):121-137
An exploration of (I) alternative perspectives toward recent innovations in reproductive technology: support for new techniques for the sake of the kind of feminist future they facilitate; unqualified opposition despite therapeutic benefit to individual women; or qualified opposition depending upon specific threats to women's interests and (II) relationships between these positions and values bound up with mothering practices. 相似文献
129.
社会主义社会对劳动保护一向给予应有的重视,从而能够有效地防止生产创伤的发生。为进一步减少生产创伤而挖掘潜力的一个方面,就是一定要研究在众多不幸事件的成因中占有相当比重的生产创伤的心理原因,这就需要把劳动安全心理学问题作为一个科学分支来进行研究,而建立这样一个科学分支本身就提出了很多问题。我们对于劳动安全心理学的理解最概括地说就是:“劳动安全心理是研究致创(创伤成 相似文献
130.
世界共产主义运动发展中和现实社会主义形成中的每一个新阶段,都伴随着马克思列宁主义理论的进一步丰富,其中也包括哲学的进一步丰富,哲学是科学世界观的核心和科学地研究自然、社会和思维的方法论根据。战后数十年的显著特点是马克思主义的研究明显地趋于活跃,尤其在社会主义国家里是如此。在这种条件下,广泛研究国外马克思主义哲学家近些年所积累的理论经验,深入系统地考察他们在继续发展马克思列宁主义哲学、阐释和宣传其基本原理和原则方面的活动,就显得极为必要了。然而,在 相似文献