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861.
Adverse impact evaluations often call for evidence that the disparity between groups in selection rates is statistically significant, and practitioners must choose which test statistic to apply in this situation. To identify the most effective testing procedure, the authors compared several alternate test statistics in terms of Type I error rates and power, focusing on situations with small samples. Significance testing was found to be of limited value because of low power for all tests. Among the alternate test statistics, the widely-used Z-test on the difference between two proportions performed reasonably well, except when sample size was extremely small. A test suggested by G. J. G. Upton (1982) provided slightly better control of Type I error under some conditions but generally produced results similar to the Z-test. Use of the Fisher Exact Test and Yates's continuity-corrected chi-square test are not recommended because of overly conservative Type I error rates and substantially lower power than the Z-test.  相似文献   
862.
OBJECTIVE: Numerous studies document that stress accelerates disease processes in a variety of diseases including HIV. As a result, investigators have developed and evaluated interventions to reduce stress as a means to improve health among persons living with HIV. Therefore, the current meta-analysis examines the impact of stress-management interventions at improving psychological, immunological, hormonal, and other behavioral health outcomes among HIV+ adults. DESIGN: This meta-analytic review integrated the results of 35 randomized controlled trials examining the efficacy of 46 separate stress management interventions for HIV+ adults (N=3,077). MAIN OUTCOME MEASURES: Effect sizes were calculated for stress processes (coping and social support), psychological/psychosocial (anxiety, depression, distress, and quality of life), immunological (CD4+ counts and viral load), hormonal (cortisol, dehydroepiandrosterone sulfate [DHEA-S], cortisol/DHEA-S ratio, and testosterone) and other behavioral health outcomes (fatigue). RESULTS: Compared to controls, stress-management interventions reduce anxiety, depression, distress, and fatigue and improve quality of life (d+s=0.16 to 0.38). Stress-management interventions do not appear to improve CD4+ counts, viral load, or hormonal outcomes compared with controls. CONCLUSION: Overall, stress-management interventions for HIV+ adults significantly improve mental health and quality of life but do not alter immunological or hormonal processes. The absence of immunological or hormonal benefits may reflect the studies' limited assessment period (measured typically within 1-week postintervention), participants' advanced stage of HIV (HIV+ status known for an average of 5 years), and/or sample characteristics (predominately male and White participants). Future research might test these hypotheses and refine our understanding of stress processes and their amelioration.  相似文献   
863.
The Computerized Propositional Idea Density Rater (CPIDR, pronounced "spider") is a computer program that determines the propositional idea density (P-density) of an English text automatically on the basis of part-of-speech tags. The key idea is that propositions correspond roughly to verbs, adjectives, adverbs, prepositions, and conjunctions. After tagging the parts of speech using MontyLingua (Liu, 2004), CPIDR applies numerous rules to adjust the count, such as combining auxiliary verbs with the main verb. A "speech mode" is provided in which CPIDR rejects repetitions and a wider range of fillers. CPIDR is a user-friendly Windows .NET application distributed as open-source freeware under GPL. Tested against human raters, it agrees with the consensus of two human raters better than the team of five raters agree with each other [r(80) = .97 vs. r(10) = .82, respectively].  相似文献   
864.
Previous research indicated that most salient, real-world objects possess natural regularities that observers commonly assume in perceptual judgments of figural orientation and interpretation. Regularities include 3-dimensionality, bilateral symmetry, and the tendency for object tops to possess more salient information than bottoms. Thus, when observers interpret randomly shaped figures, they reliably impose volume, bilateral symmetry, and top and front orientation directions, even when figures are 2-dimensional and asymmetric. We confirmed generalizability for observers to assume these regularities with stimuli that vary in complexity, and we found evidence supporting another regularity, that of symmetry verticality (symmetry about a vertical axis). Findings support use of a family of perceptual heuristics corresponding to natural regularities that constrain stimulus indeterminacy and help guide judgment of object orientation and interpretation.  相似文献   
865.
Many people believe that an informed and thoughtful citizenry is essential to the maintenance of democratic ideals within the United States and the spread of those ideals abroad. Since the September 11, 2001, terrorist attacks, the evidence that Americans consider issues of human dignity and rights when making judgments about the U.S. government's war on terror has been mixed. In our study, we assessed the relative contributions of ideological, belief, and cognitive-motivational factors to the prediction of human rights and civil liberties attitudes. Individuals scoring high on measures of right-wing authoritarianism (RWA) and the belief that the structure of knowledge is simple were the most likely to support restrictions on human rights and civil liberties as part of the war on terror. In a subsequent regression analysis, individuals scoring higher on personal need for structure or exhibiting lower levels of epistemological belief complexity tended to score higher on RWA. Additionally, men were generally more likely to support restrictions on rights and liberties and to score higher on RWA than were women.  相似文献   
866.
Infants' prelinguistic vocalizations are rarely considered relevant for communicative development. As a result, there are few studies of mechanisms underlying developmental changes in prelinguistic vocal production. Here we report the first evidence that caregivers' speech to babbling infants provides crucial, real-time guidance to the development of prelinguistic vocalizations. Mothers of 9.5-month-old infants were instructed to provide models of vocal production timed to be either contingent or noncontingent on their infants' babbling. Infants given contingent feedback rapidly restructured their babbling, incorporating phonological patterns from caregivers' speech, but infants given noncontingent feedback did not. The new vocalizations of the infants in the contingent condition shared phonological form but not phonetic content with their mothers' speech. Thus, prelinguistic infants learned new vocal forms by discovering phonological patterns in their mothers' contingent speech and then generalizing from these patterns.  相似文献   
867.
There is growing evidence that working memory, episodic/semantic memory, and procedural memory all play important roles in at least some types of category learning. Little is known, however, about the role of the perceptual representation memory system (PRS). Two experiments are reported that provide evidence that under certain conditions, the PRS, by itself, is sufficient to mediate category learning. Both experiments compared performance in (A, not A) and (A, B) prototype distortion category-learning tasks, in which category exemplars are created by randomly distorting one category prototype in the (A, not A) conditions or two prototypes in the (A, B) conditions. Results showed that (A, not A) performance was more sensitive to prototype similarity and less affected by the removal of feedback than (A, B) performance. These results support the hypothesis that (A, not A) performance was mediated by the PRS, but that (A, B) performance recruited other memory systems.  相似文献   
868.
Human syntax acquisition involves a system that can learn constraints on possible word sequences in typologically-different human languages. Evaluation of computational syntax acquisition systems typically involves theory-specific or language-specific assumptions that make it difficult to compare results in multiple languages. To address this problem, a bag-of-words incremental generation (BIG) task with an automatic sentence prediction accuracy (SPA) evaluation measure was developed. The BIG–SPA task was used to test several learners that incorporated n-gram statistics which are commonly found in statistical approaches to syntax acquisition. In addition, a novel Adjacency–Prominence learner, that was based on psycholinguistic work in sentence production and syntax acquisition, was also tested and it was found that this learner yielded the best results in this task on these languages. In general, the BIG–SPA task is argued to be a useful platform for comparing explicit theories of syntax acquisition in multiple languages.  相似文献   
869.
Intuitively it has seemed to many that our concepts conscious state and conscious creature are sharp rather than vague, that they can have no borderline cases. On the other hand, many who take conscious states to be identical to, or realized by, complex physical states are committed to the vagueness of those concepts. In the paper I argue that conscious state and conscious creature are sharp by presenting four necessary conditions for conceiving borderline cases in general, and showing that some of those conditions cannot be met with conscious state. I conclude that conscious state is sharp, and the conclusion is then extended to conscious creature. The paper ends with a brief discussion of some implications.
Michael V. AntonyEmail:
  相似文献   
870.
Those familiar with contemporary continental philosophy know well the defenses Husserlians have offered of Husserl’s theory of inner time-consciousness against post-modernism’s deconstructive criticisms. As post-modernism gives way to Deleuzean post-structuralism, Deleuze’s Le bergsonisme has grown into the movement of Bergsonism. This movement, designed to present an alternative to phenomenology, challenges Husserlian phenomenology by criticizing the most “important… of all phenomenological problems.” Arguing that Husserl’s theory of time-consciousness detailed a linear succession of iterable instants in which the now internal to consciousness receives prejudicial favor, Bergsonism concludes that Husserl derived the past from the present and cannot account for the sense of the past, which differs in kind from the present. Consequently, everything on Husserl’s account remains present and his theory cannot accommodate for time’s passage. In this paper, I renew the Husserlian defense of Husserl’s theory of time-consciousness in response to the recent movement of Deleuzean Bergsonism. Section one presents Bergsonism’s notion of the past in general and its critique of Husserl’s theory of time-consciousness. Section two presents a rejoinder to Bergsonism’s critique of Husserl, questioning (1) its understanding of the living-present as linearly extended, (2) its conflation of the living-present with Husserl’s early schema-apprehension interpretation, and (3) its failure to grasp Husserl’s revised understanding of primary memory as a result of (2). In conclusion, I suggest that Husserl’s theory of retention might articulate a notion of the past more consistent with Bergson than Bergsonism itself.
Michael R. KellyEmail:
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