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31.
The similarity of documents in a large database of published Fractals articles was examined for redundancy. Three different text matching techniques were used on published Abstracts to identify redundancy candidates, and predictions were verified by reading full text versions of the redundancy candidate articles. A small fraction of the total articles in the database was judged to be redundant. This was viewed as a lower limit, because it excluded cases where the concepts remained the same, but the text was altered substantially. Far more pervasive than redundant publications were publications that did not violate the letter of redundancy but rather violated the spirit of redundancy. There appeared to be widespread publication maximization strategies. Studies that resulted in one comprehensive paper decades ago now result in multiple papers that focus on one major problem, but are differentiated by parameter ranges, or other stratifying variables. This ‘paper inflation’ is due in large part to the increasing use of metrics (publications, patents, citations, etc) to evaluate research performance, and the researchers’ motivation to maximize the metrics. The views in this paper are solely those of the authors, and do not necessarily represent the views of the Department of the Navy or any of its components, UNAM, University of Virginia or University of Karlsruhe.  相似文献   
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The authors trained black-capped chickadees (Poecile atricapilla) in an operant discrimination with exemplars of black-capped and Carolina chick-a-dee calls, with the goal of determining whether the birds memorized the calls of conspecifics and heterospecifics or classified the calls by species. Black-capped calls served as both rewarded (S+) and unrewarded (S-) stimuli (the within-category discrimination), whereas Carolina chick-a-dee calls served as S-s (the between-category discrimination) in the black-capped chick-a-dee call S+ group. The Carolina call S+ group had Carolina calls as S+s and S-s (within-category) and black-capped calls as S-s (between-category). Both groups discriminated between call categories faster than within a call category. In 2 subsequent experiments, both S+ groups showed transfer to novel calls and propagation back to between-category calls. The results favor the hypothesis that the acoustically similar social calls of the 2 species constitute separate open-ended categories.  相似文献   
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Hypothermic rats at rectal temperatures below 30° C showed decreased duration of bar pressing for intracranial self-stimulation in lateral hypothalamic sites. The same effect was found in hungry rats. Both with cooling and hunger, decreased durations were accompanied by decreased thresholds. The threshold changes in hypothermic rats exceeded 12 μA in some cases. The results are relevant to explanations of why animals turn off rewarding brain stimulation. Particular attention is given to the possibility that cooling enhances neural activity in facilitatory connections between positive and aversive systems.  相似文献   
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A peak shift on a line-tilt continuum   总被引:1,自引:1,他引:0       下载免费PDF全文
Pigeons were trained to discriminate the presence or absence of a vertical line, and their performance on a subsequent generalization test was compared with that of other pigeons trained to discriminate a vertical from a 45° line. On the generalization gradient after discrimination training, the presence/absence discrimination group showed a peak at 0° (vertical) while the peak for the 0°/45° discrimination group shifted from 0° in a direction away from the 45° line. The results, discussed in connection with a recent suggestion about the role of color in the peak-shift effect, are interpreted as supporting the generality of the phenomenon.  相似文献   
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Research on framing effects has revealed cases where the type of outcome at risk (e.g., human lives vs. animal lives) affects the magnitude of the framing effect. Some authors have appealed to the shape of the value function as predicting when framing effects will occur: The more valuable the outcome type, the more nonlinear its value function, and the larger the resulting framing effect (Levin & Chapman, 1990). However, having a more or less nonlinear value function cannot explain situations in which participants strongly prefer the same option in both frames. Another factor that may be at work in these types of outcome effects is an aspiration level (AL; Lopes, 1987; Schneider, 1992), which determines how acceptable the options are and combines (or competes) with the risk attitude encouraged by frame. The results described here indicate that differences in the shape of the value function between outcome types are evident but are inconsistent between framed losses and gains, though nonlinearity in the value function can be increased with a manipulation that also encourages framing effects. The results also demonstrate that an AL can lead to the same predominant risk preference in the positive and negative frame. These findings indicate that the shape of the value function and the AL each play a role in outcome type interactions with frame, and in some cases, a combination of the two factors may be at work.  相似文献   
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Rips LJ  Asmuth J  Bloomfield A 《Cognition》2008,106(2):940-951
According to one theory about how children learn the meaning of the words for the positive integers, they first learn that "one," "two," and "three" stand for appropriately sized sets. They then conclude by inductive inference that the next numeral in the count sequence denotes the size of sets containing one more object than the size denoted by the preceding numeral. We have previously argued, however, that the conclusion of this Induction does not distinguish the standard meaning of the integers from nonstandard meanings in which, for example, "ten" could mean set sizes of 10, 20, 30,... elements. Margolis and Laurence [Margolis, E., & Laurence, S. (2008). How to learn the natural numbers: Inductive inference and the acquisition of number concepts. Cognition, 106, 924-939] believe that our argument depends on attributing to children "radically indeterminate" concepts. We show, first, that our conclusion is compatible with perfectly determinate meanings for "one" through "three." Second, although the inductive inference is indeed indeterminate - which is why it is consistent with nonstandard meanings - making it determinate presupposes the constraints that the inference is supposed to produce.  相似文献   
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Paul Bloomfield 《Ratio》2008,21(3):241-259
A central problem in moral theory is how it is to be defended against those who think that there is no harm in being immoral, and that immorality can be in one's self‐interest, assuming the perpetrator is not caught and punished. The argument presented here defends the idea that being immoral prevents one from having self‐respect. If it makes sense to think that one cannot be happy without self‐respect, then the conclusion follows that one cannot be both immoral and happy. Immorality is harmful because its self‐disrespecting nature keeps immoralists from being happy. This is the harm of immorality.  相似文献   
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