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Four pigeons were exposed to several nonindependent concurrent variable-interval schedules of reinforcement. One schedule component required a keypecking response; the other component required a treadlepressing response. The birds matched the ratio of their behavior (as measured by responses and time) between the two topographically different responses to the ratio of reinforcement in those two components. When additional foods not contingent on a keypeck or treadle-press were then added, the birds matched time spent in the components to total rates of food delivered in those components; response matching was somewhat disrupted. The matching law, developed under concurrent variable-interval schedules requiring similar responses, can thus account for choice behavior involving topographically different responses. 相似文献
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Astuti R Solomon GE Carey S 《Monographs of the Society for Research in Child Development》2004,69(3):1-135, vii-viii; discussion 136-61
How different are the concepts held by children who grow up in a North American middle class neighborhood and by children who grow up in a rural Malagasy fishing village? By probing Malagasy children's and adults' conceptual representations of human and animal kind, biological inheritance, innate potential and family relations, the studies presented in this Monograph address current debates about the acquisition and the nature of concepts in the domains of folkbiology and folksociology. Cross-cultural and developmental studies of this kind bear on the hypothesis that conceptual development in these domains is supported and constrained by innate conceptual content. If so, one would expect cross-cultural universality in the relevant adult concepts and their early emergence in childhood regardless of widely different input conditions. We chose to conduct these studies among the Vezo of Madagascar because the ethnographic literature has attributed to them folkbiological and folksociological theories that are radically different, even in commensurable, with those of North American adults. Vezo therefore provide a challenging test for the innate conceptual constraints hypothesis.Four studies probed aspects of biological and sociological reasoning of Vezo children, adolescents and adults through a number of adoption scenarios. Despite ethnographic reports to the contrary, we found cross-cultural convergence in adult concepts of biological inheritance, but the pattern of development of this concept differed greatly from that seen in North America. Moreover, in agreement with the ethnographic literature, we found that Vezo adults have constructed a distinctive theory of social group identity. However, we found that children's reasoning in this domain is under the influence of endogenous constraints that are overturned in the course of development. Finally, we found cross-cultural convergence in adults' concept of species kind, as well as evidence for the early emergence of this concept. In light of these findings, we discuss the nature of the constraints on children's conceptual representations, the developmental process through which the adults' concepts are constructed, and relations between Vezotheories of folkbiology and folksociology. 相似文献
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Enthusiasm for interventions designed to improve organizational quality has far outpaced interest in assessing their effects. This article describes two procedures for systematic quality assessment. First, distributional assessment provides a way to monitor individual, group or unit performance by establishing real and maximum‐feasible parameters. Second, a cost assessment system based on utility analysis provides a way to assign dollar values and benefits to quality interventions targeted at specific jobs and job functions. Both procedures are described and illustrated. They resolve a long‐standing problem with quality assessment, arising from the difficulty of accounting for situational influences which can constrain the effects of interventions designed to improve organizational performance, product or service delivery, and customer satisfaction. 相似文献
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