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The authors used recursive partitioning methods to identify combinations of baseline characteristics that predict 2-year physical activity success in each of 3 physical activity interventions delivered in the multisite Activity Counseling Trial. The sample consisted of 874 initially sedentary primary care patients, ages 35-75 years, who were at risk for cardiovascular disease. Predictors of 2-year success were specific to each intervention and represented a range of domains, including physiological, demographic, psychosocial, health-related, and environmental variables. The results indicate how specific patient subgroups (e.g., obese, unfit individuals; high-income individuals in stable health) may respond differently to varying levels and amounts of professional assistance and support. The methods used provide a practical first step toward identifying clinically meaningful patient subgroups for further systematic investigation.  相似文献   
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Children's perception of scale and contour in melodies was investigated in five studies. Experimental tasks included judging transposed renditions of melodies (Studies 1 and 3), discriminating between transposed renditions of a melody (Study 2), judging contour-preserving transformations of melodies (Study 4), and judging similarity to a familiar target melody of transformations preserving rhythm or rhythm and contour (Study 5). The first and second studies showed that young children detect key transposition changes even in familiar melodies and they perceive similarity over key transpositions even in unfamiliar melodies. Young children also are sensitive to melodic contour over transformations that preserve it (Study 5), yet they distinguish spontaneously between melodies with the same contour and different intervals (Study 4). The key distance effect reported in the literature did not occur in the tasks of this investigation (Studies 1 and 3), and it may be apparent only for melodies shorter or more impoverished than those used here.  相似文献   
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The knew-it-all-along effect is investigated by comparing pre- and post-election predictions of subjects concerning three electoral races in the November 1984 elections. The results revealed that when the outcomes of the predictions are known, subjects recall having assigned higher probabilities and percentages to the actual winners of each election, remember having more confidence in the accuracy of these percentages, and claim to have had more knowledge of the candidates than they had before the election. The results were consistent across all three elections and in both repeated-measures and between-pups designs, suggesting that the knew-it-all-along effect is a very robust one. Two underlying processes are hypothesized to account for these results: the availability heuristic and an increase in confidence explanation.  相似文献   
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A 47-year-old right-handed man underwent craniotomy for clipping of an aneurism at the trifurcation of the left middle cerebral artery. Subsequently, he suffered a left hemisphere CVA after which his speech and language resembled that of Broca's aphasia with accompanying apraxia of speech. Medical, behavioral, and acoustical data amassed over a period of several months indicated numerous contraindications to traditional diagnoses of Broca's aphasia, apraxia of speech, and dysarthria. Ultimately, it was determined that the patient had a selective impairement of phonation or laryngeal apraxia. This was illustrated dramatically when he was taught to use an electrolarynx which allowed him to bypass his disrupted phonatory system. Speaking with the electrolarynx, the patient communicated normally. Any semblance of Broca's aphasia disappeared. Supralaryngeal articulation was normal; apraxia of speech behaviors were absent. This case report indicates that dissociation of oral and laryngeal gestures due to brain injury is possible. Mechanisms underlying such a dissociation for this case are reviewed. The possibility of discrete center lesions in the frontal motor association area causing different types of apraxia of speech is discussed.  相似文献   
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The analytics of continuing conflict   总被引:10,自引:0,他引:10  
Jack Hirshleifer 《Synthese》1988,76(2):201-233
Individuals, groups, or nations — if rational and self-interested — will be balancing on the margin between two alternative ways of generating income: (1) peaceful production and exchange, versus (2) appropriative efforts designed to seize resources previously controlled by others (or to defend against such invasions). Both production and appropriation, on the assumption here, are entirely normal lines of activity engaged in to the extent that doing so seems profitable.The general-equilibrium steady-state model involves a resource partition function, a social production function, a combat power function, and an income distribution equation. Solutions were obtained under thesymmetrical Cournot protocol and two alternativeasymmetrical assumptions: the familiar Stackelberg condition and a more novel hierarchical protocol called Threat-and-Promise. The analysis demonstrates that, in contrast with the harmonistic bias of orthodox economic theory, a general-equilibrium model can also encompass the hostile and destructive interactions that characterize real-world social relations.The efforts of men are utilized in two different ways: they are directed to the production or transformation of economic goods, or else to the appropriation of goods produced by others.Vilfredo ParetoI thank the Ford Foundation for assistance in supporting this research.  相似文献   
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