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1.
The one-box federated search of databases brings as many challenges as promises to database searching, especially in terms of adapting these systems to user needs and the effects this new mode of searching will have on users' research behaviors. This issue of “The Balance Point” presents several librarians with strong interests in reference and instruction, who tell the story of adapting a federated search system for their libraries and reflect upon how federated searching can change the way students do research and on the implications federated searching has on information literacy skills and the quality of results found.  相似文献   

2.
The amount of online scholarly information is rapidly expanding and residing in increasingly disparate sources, while user behavior is evolving to demand single search interfaces like Google. Federated search enables librarians to meet these challenges by supplying efficient, effective access and delivery of the most relevant content from diverse sources to their patrons. Introducing the ability to simultaneously search multiple databases, however, can quickly lead to information overload. Dynamic categorization of search results is one way to manage and organize the large volume of content returned. This article will examine various federated search technologies and important considerations that librarians should undertake when evaluating federated search applications, as well as address how SwetsWise Searcher supports the fundamental aspects of federated searching within that context.  相似文献   

3.
With the ubiquity of federated search tools as viable solutions for students and researchers to search across external sources and internal repositories, users have become more sophisticated in their application of this technology. With the goal of optimizing the user experience of its newly introduced federated search offering, Endeavor Information Systems employed usability testing to gain insights into the critical requirements of librarians and information professionals for this solution. The results of this analysis, conducted in concert with market research and customer focus groups, and their relevance to Endeavor's federated search technology are the focus of this article.  相似文献   

4.
Fei Xu 《Serials Review》2009,35(4):235-241
During 2009, the Hilton M. Briggs Library, South Dakota State University, went live with MetaLib, a federated search engine from Ex Libris. This paper presents the implementation process, addresses resource accessibility issues, and suggests a number of resources that can be consulted about these issues. Readers can apply similar strategies to projects involving federated search systems, as many implementation projects involve the same basic considerations presented here. The author did not find any studies specifically focused on configurations of MetaLib resources, so this content should be singularly useful.  相似文献   

5.
Between late 2004 and January 2006, Texas A&M University Libraries implemented Metalib®, Ex Libris'â?¢ federated search software. This article outlines the implementation process, including selection criteria, implementation decisions, and staff and faculty training techniques. Special attention is paid to describing search configuration changes and user interface modifications. The implementers made many of their implementation choices based on usability training, which is briefly described. The article ends with a set of conclusions as to successes and failures in the project and a list of recommended features to look for in selecting a federated search system.  相似文献   

6.
Fei Xu 《Serials Review》2013,39(4):235-241
Abstract

During 2009, the Hilton M. Briggs Library, South Dakota State University, went live with MetaLib, a federated search engine from Ex Libris. This paper presents the implementation process, addresses resource accessibility issues, and suggests a number of resources that can be consulted about these issues. Readers can apply similar strategies to projects involving federated search systems, as many implementation projects involve the same basic considerations presented here. The author did not find any studies specifically focused on configurations of MetaLib resources, so this content should be singularly useful.  相似文献   

7.
The Muse Metasearch Engine is not just federated search. This paper discusses search and finding issues, focusing on the complexities and difficulties of these processes, and then describes how Muse is the “middle ground of search.” Muse pulls together content from multiple databases, repositories, and search engines—the most critical factor in the success of “publishing” comprehensive content. The author then describes what is needed to provide a comprehensive metasearch publishing environment.  相似文献   

8.
A doctoral student approached the column editor and suggested that an update on a “The Balance Point” column entitled “The One-Box Challenge: Providing a Federated Search That Benefits the Research Process” (2006) would be of interest and useful to readers, and the editor agreed. Contributors to the original column were asked to reflect upon their experiences with federated searching, including successes and failures over the past 10 years, and to provide insights into future challenges and issues. This edition of “The Balance Point” focuses on the ongoing challenges, lessons learned, possible future directions, and issues involved in providing one-box searching to library patrons.  相似文献   

9.
Serials Digest     
Abstract

A collection manager and an acquisition librarian discuss difficult decisions to be made regarding electronic resources and associated value-added services. Balancing budget constraints with patron demands for easy access to information requires librarians to reevaluate assumptions about the electronic products and associated services that have quickly become staples of library life, even as these staples become increasingly untenable. The authors scrutinize the cost/benefit of continuing value-added services, such as providing access to abstracting and indexing tools and full MARC cataloging records of journal titles, as well as considering the adoption of new services such as federated search engines and link resolvers.  相似文献   

10.
This article provides a method to estimate search costs in a differentiated product environment in which consumers are uncertain about the utility distribution. Consumers learn about the utility distribution by Bayesian updating their Dirichlet process prior beliefs. The model provides expressions for bounds on the search costs that can rationalize observed search and purchasing behavior. Using individual-specific data on web browsing and purchasing behavior for MP3 players sold online we show how to use these bounds to estimate search costs as well as the parameters of the utility distribution. Our estimates indicate that search costs are sizable. We show that ignoring consumer learning while searching can lead to severely biased search cost and elasticity estimates.  相似文献   

11.
We consider the problem of constructing search designs for 3m factorial designs. By using projection properties of some three-level orthogonal arrays, some search designs are obtained for 3 ? m ? 11. The new obtained orthogonal search designs are capable of searching and identifying up to four two-factor interactions and estimating them along with the general mean and main effects. The resulted designs have very high searching probabilities; it means that besides the well-known orthogonal structure, they have high ability in searching the true effects.  相似文献   

12.
Since the introduction of the search design by Srivastava [Designs for searching non-negligible effects. In: Srivastava, editor. A survey of statistical design and linear models. Amsterdam: North-Holland, Elsevier; 1975. p. 507–519], construction of such designs has been considered by many researchers. The efficient performances of constructed search designs in terms of parameter estimation and search ability of parameters have also been investigated by several authors. They have proposed suitable optimality measures such as DD- and AD-optimality for estimation in the early stage of search design construction. Moreover, since 1990s, some criteria have been developed to evaluate search performance of a design. Although these criteria are useful none of them is able to evaluate both estimation and search efficiency of a design simultaneously. In this paper, we propose dual-task criteria to deal with searching and estimating performances of search designs. These compound criteria are weighted multiplication of estimation and search suitable criteria. They will be used for design comparison and the results will be presented.  相似文献   

13.
The results of a computer search for saturated designs for 2n factorial experiments with n runs is reported, (where n = 2 mod 4). A complete search of the design space is avoided by focussing on designs constructed from cyclic generators. A method of searching quickly for the best generators is given. The resulting designs are as good as, and sometimes better than, designs obtained via search algorithms reported in the literature. The addition of a further factor having three levels is also considered. Here, too, a complete search is avoided by restricting attention to the most efficient part of the design space under p-efficiency.  相似文献   

14.
Abstract

This article develops a method to estimate search frictions as well as preference parameters in differentiated product markets. Search costs are nonparametrically identified, which means our method can be used to estimate search costs in differentiated product markets that lack a suitable search cost shifter. We apply our model to the U.S. Medigap insurance market. We find that search costs are substantial: the estimated median cost of searching for an insurer is $30. Using the estimated parameters we find that eliminating search costs could result in price decreases of as much as $71 (or 4.7%), along with increases in average consumer welfare of up to $374.  相似文献   

15.
Abstract

This paper considers a new model in search theory to find a randomly located target in the 3-dimensional space. An approximation algorithm that facilitates searching procedures for searchers or robots is presented. The expected time to detect the target is also proved. The statistical analysis by calculating the optimal search strategy which minimizes the time to detect the target, assuming trivariate standard normal distribution is provided, and the technique by flowcharts is designed as well. The effectiveness of this strategy is illustrated by introducing an application from real world.  相似文献   

16.
Pattern Matching     
An important subtask of the pattern discovery process is pattern matching, where the pattern sought is already known and we want to determine how often and where it occurs in a sequence. In this paper we review the most practical techniques to find patterns of different kinds. We show how regular expressions can be searched for with general techniques, and how simpler patterns can be dealt with more simply and efficiently. We consider exact as well as approximate pattern matching. Also we cover both sequential searching, where the sequence cannot be preprocessed, and indexed searching, where we have a data structure built over the sequence to speed up the search.  相似文献   

17.
This article addresses the issue of parameter estimation in linear system in the presence of Gaussian noises, under which the random number searching algorithm (LJ (Luus and Jaakola) algorithm) is combined with the Rao-Blackwellised particle filter (RBPF) algorithm. This yields the so-called RBPF algorithm based on LJ (RBPF-LJ). Unlike the mature alternatives of generic particle filter, the parameter particles of RBPF-LJ are set as random numbers that search in the parameter value scope, which is regulated based on the estimation result to track the changes of the unknown parameter. The contrasting simulations show that the proposed RBPF-LJ outperform the RBPF as well as the particle filter based on kernel smoothing contraction algorithm on the estimation of the dynamically linear or nonlinear parameter and it can obtain the similar estimation results on the static parameter if some coefficients are regulated.  相似文献   

18.
Search designs are considered for searching and estimating one nonzero interaction from the two and three factor interactions under the search linear model. We compare three 12-run search designs D1, D2, and D3, and three 11-run search designs D4, D5, and D6, for a 24 factorial experiment. Designs D2 and D3 are orthogonal arrays of strength 2, D1 and D4 are balanced arrays of full strength, D5 is a balanced array of strength 2, and D6 is obtained from D3 by deleting the duplicate run. Designs D4 and D5 are also obtained by deleting a run from D1 and D2, respectively. Balanced arrays and orthogonal arrays are commonly used factorial designs in scientific experiments. “Search probabilities” are calculated for the comparison of search designs. Three criteria based on search probabilities are presented to determine the design which is most likely to identify the nonzero interaction. The calculation of these search probabilities depends on an unknown parameter ρ which has a signal-to-noise ratio form. For a given value of ρ, Criteria I and II are newly proposed in this paper and Criteria III is given in Shirakura et al. (Ann. Statist. 24 (6) (1996) 2560). We generalize Criteria I–III for all values of ρ so that the comparison of search designs can be made without requiring a specific value of ρ. We have developed simplified methods for comparing designs under these three criteria for all values of ρ. We demonstrate, under all three criteria, that the balanced array D1 is more likely to identify the nonzero interaction than the orthogonal arrays D2 and D3, and the design D4 is more likely to identify the nonzero interaction than the designs D5 and D6.The methods of comparing designs developed in this paper are applicable to other factorial experiments for searching one nonzero interaction of any order.  相似文献   

19.
The use of optimal orthogonal array latin hypercube designs is proposed. Orthogonal arrays were proposed for constructing latin hypercube designs by Tang (1993). Such designs generally have better space filling properties than random latin hypercube designs. Even so, these designs do not necessarily fill the space particularly well. As a result, we consider orthogonal-array-based latin hypercube designs that try to achieve optimality in some sense. Optimization is performed by adapting strategies found in Morris & Mitchell (1995) and Ye et al. (2000). The strategies here search only orthogonal-array-based latin hypercube designs and, as a result, optimal designs are found in a more efficient fashion. The designs found are in general agreement with existing optimal designs reported elsewhere.  相似文献   

20.
A common data mining task is the search for associations in large databases. Here we consider the search for “interestingly large” counts in a large frequency table, having millions of cells, most of which have an observed frequency of 0 or 1. We first construct a baseline or null hypothesis expected frequency for each cell, and then suggest and compare screening criteria for ranking the cell deviations of observed from expected count. A criterion based on the results of fitting an empirical Bayes model to the cell counts is recommended. An example compares these criteria for searching the FDA Spontaneous Reporting System database maintained by the Division of Pharmacovigilance and Epidemiology. In the example, each cell count is the number of reports combining one of 1,398 drugs with one of 952 adverse events (total of cell counts = 4.9 million), and the problem is to screen the drug-event combinations for possible further investigation.  相似文献   

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