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161.
An assertion of high conditional probability or, more briefly, an HCP assertion is a statement of the type: The conditional probability of B given A is close to one. The goal of this paper is to construct logics of HCP assertions whose conclusions are highly likely to be correct rather than certain to be correct. Such logics would allow useful conclusions to be drawn when the premises are not strong enough to allow conclusions to be reached with certainty. This goal is achieved by taking Adams" (1966) logic, changing its intended application from conditionals to HCP assertions, and then weakening its criterion for entailment. According to the weakened entailment criterion, called the Criterion of Near Surety and which may be loosely interpreted as a Bayesian criterion, a conclusion is entailed if and only if nearly every model of the premises is a model of the conclusion. The resulting logic, called NSL, is nonmonotonic. Entailment in this logic, although not as strict as entailment in Adams" logic, is more strict than entailment in the propositional logic of material conditionals. Next, NSL was modified by requiring that each HCP assertion be scaled; this means that to each HCP assertion was associated a bound on the deviation from 1 of the conditional probability that is the subject of the assertion. Scaling of HCP assertions is useful for breaking entailment deadlocks. For example, it it is known that the conditional probabilities of C given A and of ¬ C given B are both close to one but the bound on the former"s deviation from 1 is much smaller than the latter"s, then it may be concluded that in all likelihood the conditional probability of C given A B is close to one. The resulting logic, called NSL-S, is also nonmonotonic. Despite great differences in their definitions of entailment, entailment in NSL is equivalent to Lehmann and Magidor"s rational closure and, disregarding minor differences concerning which premise sets are considered consistent, entailment in NSL-S is equivalent to entailment in Goldszmidt and Pearl"s System-Z
+. Bacchus, Grove, Halpern, and Koller proposed two methods of developing a predicate calculus based on the Criterion of Near Surety. In their random-structures method, which assumed a prior distribution similar to that of NSL, it appears possible to define an entailment relation equivalent to that of NSL. In their random-worlds method, which assumed a prior distribution dramatically different from that of NSL, it is known that the entailment relation is different from that of NSL. 相似文献
162.
Much research has supported the assertion of Hooper, et al.'s 1994 claims that specific stimuli perform better than others in eliciting well-developed written responses; however, previous research was conducted with raters who were aware of the hypotheses. The present study of 29 middle school children validated previous support for Hooper, et al.'s assertions by implementing blind rating and, once again, finding that significant differences between Hooper-like and non-Hooper-like prompts existed for structural items but not for items of mechanics. 相似文献
163.
Gellatly A Cole G 《Journal of experimental psychology. Human perception and performance》2000,26(3):889-899
In 4 experiments, the authors investigated accuracy of detecting a target among nontargets. In some experiments, the target was a second-order square of stationary lines on a background of downward-moving lines, and nontargets were second-order squares of upward-moving lines. In other experiments, target and nontarget squares and background were shades of gray. The principal comparison was between "new" and "old" object displays. In new-object displays, search items appeared abruptly and one might be a target. In old-object displays, search items appeared abruptly, and after a delay one might become a target. Search displays in both conditions terminated shortly after target onset. Except when target onset was associated with the sole luminance change in a display, targets were much better detected in new- than in old-object displays. It is suggested that object onsets elicit a brief stimulus-driven enhancement of attention to the new objects. 相似文献
164.
Covert face recognition in neurologically intact participants 总被引:1,自引:0,他引:1
Prosopagnosic patients may maintain some ability to recognize familiar faces, although they remain unaware of this ability.
This phenomenon – called covert face recognition – was investigated in neurologically intact participants, using priming techniques.
Participants were quicker to indicate that a target-name was familiar when the preceding prime-face belonged to the same person
compared with an unrelated familiar person. This was observed both when prime-faces could be recognized overtly and when they
were presented too briefly to be recognized overtly (Exps. 1 and 2). Thus, covert face recognition was observed in neurologically
intact participants. In Exp. 3, participants were quicker to recognize a familiar face when that person's face had been seen
previously, but only when it had been recognized overtly on the first encounter. These results are interpreted within the
framework of an interactive activation model of face recognition.
Received: 21 September 1998 / Accepted: 2 March 1999 相似文献
165.
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168.
Cole GW 《The Psychoanalytic quarterly》2005,74(4):977-987
An invitation to participate in a conference, especially the phrase, "we hope that your [contribution] might deal with same-sex love," reveals the persistent, lingering effects of the creation of the categories homosexual and heterosexual. Analysis of the phrase suggests a fantasy condensed in the invitation: that a gay psychoanalyst loves and works differently than his heterosexual colleagues and that this difference is determined by his sexual orientation. Approaching the creation of these categories as a symptom of a process of repudiation and projection, the author seeks to begin identifying and sorting through the projected psychic contents that keep these categories' specious effects alive. 相似文献
169.
Lynam DR Caspi A Moffitt TE Raine A Loeber R Stouthamer-Loeber M 《Journal of abnormal child psychology》2005,33(4):431-443
The present study examines the relation between psychopathy and the Big Five dimensions of personality in two samples of adolescents. Specifically, the study tests the hypothesis that the aspect of psychopathy representing selfishness, callousness, and interpersonal manipulation (Factor 1) is most strongly associated with low Agreeableness, whereas the aspect of psychopathy representing impulsivity, instability, and social deviance (Factor 2) is associated with low Agreeableness, low Conscientiousness, and high Neuroticism. Data from 13- and 16-year-old boys and their mothers from two samples of the Pittsburgh Youth Study are used to test these hypotheses. Results were consistent across age and rating source in supporting the initial hypotheses, providing support for the construct of juvenile psychopathy and the interpretation of psychopathy as a constellation of traits drawn from a general model of personality functioning. 相似文献
170.
Swaisgood RR White AM Zhou X Zhang G Lindburg DG 《Journal of comparative psychology (Washington, D.C. : 1983)》2005,119(3):325-334
This study investigated the responses of 14 giant pandas (Ailuropoda melanoleuca) to 5 enrichment items (3 manipulable objects, 2 feeding devices) that possess different properties affording varying behavioral opportunities. Enrichment items were quantitatively described by using 12 properties. Pandas displayed no preferences among the 5 enrichment treatments, all of which had similar positive effects on behavioral measures of well-being (behavioral diversity, stereotypy). However, each item promoted a distinct behavioral profile, readily mapped onto the enrichment's properties. These results suggest that it may be important to stimulate behavioral diversity but that specific behaviors or enrichment properties are not required. The unique behavioral topography seen with these enrichments also suggests that providing multiple enrichments with varying properties will maximize overall behavioral diversity. 相似文献