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11.
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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Stress in time     
The goals of this research were to determine whether speakers adjust the stress patterns of words within sentences to create an alternation between strong and weak beats and to explore whether this rhythmic alternation contributes to the characteristics stress differences between two major lexical categories of English. Two experiments suggested that speakers do alter lexical stress in accordance with rhythmic biases. When speakers produced disyllabic pseudowords in sentence contexts, they were more likely to place stress on the first syllable when the pseudoword was preceded by a weak stress and followed by a strong one than when the strong stress preceded and the weak followed. This occurred both when the pseudowords served as nouns and when they served as verbs. Text analyses further revealed that weakly stressed elements precede nouns more often than verbs, whereas such elements follow verbs more often than nouns. Thus, disyllabic nouns are more likely than disyllabic verbs to occupy contexts biased toward trochaic rhythm, a finding consistent with leftward dominant stress in disyllabic English nouns. The history of stress changes in English nouns and verbs also conforms with the view that rhythmic context may have contributed to the evolution of stress differences. Together, the findings suggest that the citation stress patterns of words may to some degree reflect adaptations of lexical knowledge to conditions of language performance.  相似文献   
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Ambient white noise (80 dB), compared with quiet (52-dB) testing conditions, improved the performance of elderly and younger subjects on simple addition. Reliable age-related interactions were found on health measures of systolic and diastolic blood pressure, as well as heart rate. Heightened sensory conditions reduced the physiological measures of arousal in the younger group, whereas significant cardiovascular reactivity was found among the older group. The results are suggestive of the potential for increased cardiovascular risk as a function of sensory stimulation in the elderly despite improvements on cognitive tasks. Additional research is needed to evaluate the multidimensional effects of extended sensory stimulation on the elderly.  相似文献   
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This investigation examined the relationship between methylphenidate (MPH) and the learning and recall of paired associations by children with attention deficit disorder with hyperactivity (ADDH). Forty-five children with ADDH were randomly assigned to one of three groups (novel, partial mastery, and mastery learning) that varied in the amount of previous learning of paired associations and participated in a double-blind, placebo-control, repeated-measures-across-dose (crossover) design. Each child received four doses of MPH (5 mg, 10 mg, 15 mg, and 20 mg) and a placebo in a random, counterbalanced sequence. The results indicated that both the rate of acquisition and accuracy in learning paired associations were significantly, but differentially, affected by MPH dose and the degree of learning mastery. The implications of these results for psychopharmacological research and the monitoring of psychostimulant effects on children's learning performance in academic settings are discussed.The authors wish to acknowledge and express their sincere appreciation to the graduate and undergraduate student members of the Children's Learning Clinic.  相似文献   
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Although there has been a considerable amount of research on simultaneous and successive processing (Luria's second functional unit) by Das and others, there have been relatively few investigations into the measurement of attention and planning (the first and third functional units, respectively). The purpose of this investigation was to examine the factorial validity of tasks designed to measure cognitive processing in each of Luria's three functional units. A sample of 112 normal fourth- and fifth-grade students were administered nine experimental tasks chosen or developed according to the theoretical components of planning, attention, simultaneous, and successive processes. Principal factor analyses (orthogonal and oblique) with rotation of four factors resulted in solutions that closely matched the anticipated groupings based on a structural analysis of the tasks. General support for the feasibility of measurement of Luria's cognitive processing model, and the need to further develop and refine these and other experimental tasks, was obtained.  相似文献   
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For decades toy choice has been a very popular measure of children's sex-role adoption. In the present study, the relations between choice of masculine, neutral, or feminine toys and other social behaviors (sex typed and non-sex typed) were examined. The social behaviors (socializing, requesting assistance, prosocial behaviors, aggressive/defensive behaviors) and toy choices of 33 preschool children were observed in their classrooms. Only two behaviors were found to be sex typed (socializing with peers and spontaneous prosocial behavior), and both of these behaviors were related to toy choice. Toy choice was also related to helping. Among boys, masculine toy choice was associated with requesting assistance from teachers. When toy choice was classified as masculine, androgynous, and feminine, only sociability toward peers was related to toy choice. The results are discussed in terms of their implications for the continued use of toy choice as a measure of sex-role adoption.The authors wish to express their gratitude to Rene Dodez for her assistance in data analysis and to the children and teachers at the Child Study Laboratory. We also appreciate the contributions of Drs. Laurie Chassin, Jerry Harris, Susan Somerville, Sharlene Wolchik, and Antonette Zeiss. This research was completed by the first author in partial fulfillment of the masters of arts degree at Arizona State University.  相似文献   
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