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Economists and management “scientists” tend to adopt a rationalistic, “black box” approach to the treatment of technological innovation, with decisions to invest in innovation being viewed as climactic acts and with the significant impact of risk and uncertainty often being disregarded. This paper examines an alternative analytical perspective: that a least the early development of technological innovation is a process of incremental decision making where managerial responses are affected by the consequences of previous decisions and by alterations in external information. The development of the “poromeric” Porvair discussed here illustrates the considerable risks that have to be borne when undertaking radical innovation, and the nature of the uncertainties, the interdependency between them and the manner in which they persist, in this case even beyond the commercialization of the new product.  相似文献   
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93 first graders (mean age 6.5 years) were given a pretest and posttest on half of the items from the Children's Embedded Figures Test. Half of the children were randomly assigned to a training condition and received a brief training procedure on visual-spatial disembedding prior to the administration of the posttest. Children in the control condition received no training. The performance of girls improved significantly more from pretest to posttest than the performance of boys. Boys and girls showed similar beneficial effects of training in addition to the benefit of direct practice. The tendency that was observed for boys to perform higher than girls on the pretest, p less than .10, was not evident on the posttest. Scores on the pretest predicted scores on a different measure of visual-spatial ability only for children in the control group. The results are interpreted in terms of current theories of sex differences in visual-spatial perception.  相似文献   
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The study compared general population samples of Jamaican children ages 6–18 years, via Jamaican versions of the Child Behavior Checklist (CBCL) parent-, teacher-, and self-report forms. Repeated measures ANOVAs with informant as a repeated measures factor, assessed base-rate problem score differences according to children’s area of residence (i.e., urban vs rural), gender, and age. No between subjects residence effects emerged for total problem score. However, adolescents self-reported higher total problem scores compared to the ratings they received from their parents and teachers. No gender total problem score effects emerged for any of the three informants, but girls received higher internalizing, and Somatic Complaints scores. Similar total problem scores across genders, and the high ratio of boys to girls in clinic samples suggest that Jamaican girls may not be receiving adequate services. Age X within subjects interactions revealed higher teacher reported problem scores for young adolescents, reflecting possible developmental changes within the classroom context and teachers’ low thresholds toward these problems. The d statistic revealed base rate syndrome, internalizing, externalizing, and total problem score differences in most Jamaican vs US sub-samples. In addition to the non-CBCL problems observed in earlier studies, these findings clearly indicate a need to ascertain syndrome structure and other psychometric properties of the Jamaican instruments.  相似文献   
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This paper was presented at the symposium dedicated to the 25th anniversary of the publication of Patrons Despite Themselves: Taxpayers and Arts Policy (Feld et al. 1983), held by the Association for Cultural Economics International, Boston, June 2008. It considers alternative means of providing indirect tax-based state support of the arts, such as the use of tax credits as opposed to tax deductions for charitable contributions, matching grants, and support applied to specific projects. It also considers the problem of broad-based changes to tax policy that have unintended consequences for arts organizations.   相似文献   
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Using data on the ‘career’ paths of one thousand ‘leading scientists’ from 1450 to 1900, what is conventionally called the ‘rise of modern science’ is mapped as a changing geography of scientific practice in urban networks. Four distinctive networks of scientific practice are identified. A primate network centred on Padua and central and northern Italy in the sixteenth century expands across the Alps to become a polycentric network in the seventeenth century, which in turn dissipates into a weak polycentric network in the eighteenth century. The nineteenth century marks a huge change of scale as a primate network centred on Berlin and dominated by German-speaking universities. These geographies are interpreted as core-producing processes in Wallerstein’s modern world-system; the rise of modern scientific practice is central to the development of structures of knowledge that relate to, but do not mirror, material changes in the system.
David M. EvansEmail:
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