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941.
Joseph G. Eisenhauer 《Teaching Statistics》2021,43(1):21-27
Statistical methods are increasingly being used to integrate findings from the ever‐expanding universe of empirical research. Meta‐analysis encompasses various techniques for synthesizing summary statistics, and mega‐analysis pools raw data across studies. This paper offers an introduction to meta‐analysis and mega‐analysis that complements the study of analysis of variance (ANOVA). After a brief conceptual discussion, we provide simple numerical examples. 相似文献
942.
A bibliography is traditionally characterized by the judgments, bounded by explicit selection criteria, made by a single compiler. Because these criteria concern the attributes ascribed to a work and the needs of readers, bibliographic work is largely conceptual even across technological eras and domains. Yet, the development of networked information services, made possible by WWW infrastructure, has enabled very large numbers of people to discover, organize, and publish information, including bibliographies. Indeed, bibliographies, or at least bibliography-like artifacts, are a common genre of website, often published by people without specialized skills in information organization who follow non-rigorous selection procedures. Nevertheless, even if the items from these lists are poorly selected and described, this publishing activity is fundamentally important because it structures information locally, creating a patchy network of secondary access points. In turn, these access points enable information discovery, the formation and development of communities of interest, the estimation of document relevance by search engines, and so on. In sum, this activity, and the enabling technical infrastructure, invites bibliographies to take on new interactive possibilities. The aim of this article is to extend the traditional view of bibliography to encompass collaborative possibilities for wide, or narrow, participation in the shaping of bibliographies and the selection of items. This is done by examining the nature of bibliography on the Web, by proposing a conceptual model that opens bibliography to participatory practices, and by discussing a case study where a team sought to develop a bibliography of electronic resources. This examination reveals splendid opportunities for expanding the notion of bibliography with participatory policies while remaining true to its ancient roots. 相似文献
943.
An operational prototype inhomogeneous distributed database system has been built to provide homogeneous access for researchers and managers of science policy to data on research projects held in three countries. The architecture is sufficiently general not only to accommodate additional countries and databases on research projects, but also to provide a general framework for other international collaborative projects aimed at the provision of information. The design exhibits an optimal compromise between sufficient data to satisfy a retrieval request and the minimal data for transmission to maintain the database. 相似文献
944.
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946.
G. H. Lander Ph.D 《Endeavour》1990,14(4)
This year marks the 50th anniversary of the preparation of the first transuranium elements, neptunium and plutonium though thus losing pride of place in the Periodic Table, uranium still has secrets to reveal. This article describes efforts to characterize the extremely subtle series of distortions that appears at low temperature in the element. Our understanding of these distortions require some of the latest ideas in diffraction physics, so that the story is a continuously evolving one. Uranium is the only element (so far) that has been found to have a spontaneous charge-density wave. 相似文献
947.
Syed Shamil B.Sc. Ph.D. C.Chem. M.R.S.C. M.I.F.S.T. Gordon G. Birch B.Sc. Ph.D. D.Sc. F.R.C.S. F.I.F.S.T. 《Endeavour》1990,14(4)
Of all the senses, that of taste is perhaps the hardest to define and quantify and elucidation of the underlying mechanisms is unrespondingly difficult. This article describes a conceptual model — at the molecular level — for the four basic taste modalities, using apparent specific volume as a fundamental parameter. It also considers possible practical applications. 相似文献
948.
Robert G. Crawford 《Information processing & management》1977,13(4):235-245
A method for updating the dictionary in a dynamic information retrieval system is presented. It is shown that as a collection changes through addition and deletion of documents, the appropriate set of index terms may be determined without complete periodic regeneration of the dictionary. Results are presented for experiments involving a complete change in collection membership, with the dynamic dictionary updating methods shown to be effective. 相似文献
949.
The level of sialic acid in the obese polymorphonuclear leukocytes (PMNL) was found to be significantly reduced as compared to normal. Activity of sialic acid degrading enzyme, sialidase, was found to be increased in the obese state. Restoration in both sialic acid content and sialidase activity was also evidenced in the PMNL of treated obese patients. 相似文献
950.