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Even though there has been a proliferation of e-society measures in recent years, analyses of the metrics of the “information society” are still far from responsive to the needs of many stakeholders and continue to suffer from a number of serious limitations. Issues in eight critical areas are briefly presented. They include: definition of the universe to be measured; definition of the objects and phenomena to include in the universe; need to establish measurements based upon solid theories; units of measurements; data sources and collection; methods of analysis and construction of indicators; target audiences; and purpose and utilization of measurements. An organized collective effort, which could provide the impetus for the development of a coherent academic field of study, is called for to address this “grand challenge.”  相似文献   

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An imperfect document selection system is represented as the analogy of a system in which symbols are selected and transmitted through a noisy channel. Provided that transmission reception uncertainties and not meaning are considered, it is suggested that one of Shannon's equations is applicable, and a single figure measure of system efficiency, Ht, is proposed.Values obtained using this new yardstick are compared with Recall/Precision values obtained for a typical system. Further research is required to test whether system “improvements” resulting in higher values of Ht are perceived as such by users.  相似文献   

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Most automated information retrieval systems operate by relating a document to a request by means of a measure of pertinance, and then retrieving the most pertinent documents for their patrons. In this paper the consistency of this operating procedure with the well known Swets Model is examined. It is shown that accepting the assumptions made by Swets would result in the possible rejection of the most pertinent documents in favor of those that are less pertinent. This conclusion is a consequence of the normality assumptions of the model, while other distributions, such as the Poisson distribution, is consistent with the standard procedure. In the course of the development, the fundamentals of decision theory and signal detection theory are reviewed.  相似文献   

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This study examined the development of individual social capital in a distributed learning community. Feld's theory of focused choice predicts that the formation of network ties is constrained by contextual factors that function as foci of activities. In our research, we examined how group assignment and location could function as such foci to influence the development of individual social capital in a distributed learning community. Given that networks with different content flows may possess different properties, we examined two different types of networks—task-related instrumental networks and non-task-related expressive networks. A longitudinal research design was used to evaluate the evolution of networks over time. Hypotheses were tested using a sample of 32 students enrolled in a distributed learning class. The results show strong support for Feld's theory. While serving as foci of activities to organize social interactions, both group assignment and geographic separation can also function to fragment a learning community.  相似文献   

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There are many cases where it is necessary to store sets of data that are variable in length, and to search these in order to satisfy requests for subsets with a common characteristic. This article presents a file structure that holds an integrated English dictionary used to locate clusters of words for presentation to an intelligent spelling error correction system. Although the emphasis has been on misspelling, the structure presented is capable of handling any other types of lumpy data provided the characteristics used in search requests can be translated into a set of integer numbers.  相似文献   

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This article shows how various meanings of a new communication technology are born or get transformed when placed in a different political context via a case study of a program organized by the Soros Foundation in 1984 to promote democratic values (the idea of an “open society”) in Hungary. This program, called the Xerox project, helped hundreds of public institutions acquire photocopy machines. Under the suppressive Hungarian regime of the 1980s the appearance of photocopy machines as a new means of copying texts had serious political consequences. By means of historical research and expert interviews, this article analyzes the nature of these consequences and examines how certain meanings and uses of photocopy machines evolved in the latter half of the 1980s.  相似文献   

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