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121.
P L Miller J S Morrow S M Powsner C A Riely 《Bulletin of the Medical Library Association》1988,76(2):131-136
An experimental computer-based bibliographic retrieval system has been implemented to explore how semantic (conceptual) relationships between MeSH terms might assist the retrieval process. To construct the experimental system's database, lists of abstracts were produced using MEDLINE. Each list contained papers discussing a specified pair of terms. Each abstract was then analyzed to determine the specific relationship(s) between the two terms discussed in that paper. The project then explored how these semantic relationships could be incorporated into the computer to enhance bibliographic retrieval. 相似文献
122.
Larry E. Stanfel 《Information processing & management》1983,19(1):37-50
Given the difficulty of designing and creating information systems of many components and interconnections, it is commonplace to find these tasks accomplished by means of a partition into subsystems. Later the distinct subsystems are made to interface with one another and an overall system is achieved. The purpose of the present paper is to point out the availability of methods for effecting the partition in optimal or approximately optimal ways. Clustering algorithms for the specific case of information systems are obtained and exemplified. 相似文献
123.
Several statistical sampling methods are evaluated for estimating the total number of relevant documents in a collection for a given query. The total number of relevant documents is needed in order to compute recall values for use in evaluating document retrieval systems. The simplest method considered uses simple random sampling to estimate the number of relevant documents. Another type of random sampling, which assigns unequal selection probabilities to the individual documents in the collection, is also investigated. An alternative approach considered uses curve fitting and extrapolation, where a smooth curve is developed which relates precision to document rank. Another curve relates a function of precision to the query-document score. In either case, the curve is extrapolated to the total number of documents in order to estimate the number of relevant documents. Empirical comparisons are made of all three methods. 相似文献
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128.
Miller CJ Miller SR Bloom JS Jones L Lindstrom W Craggs J Garcia-Barrera M Semrud-Clikeman M Gilger JW Hynd GW 《Annals of dyslexia》2006,56(1):83-102
The double-deficit hypothesis of dyslexia posits that reading deficits are more severe in individuals with weaknesses in phonological awareness and rapid naming than in individuals with deficits in only one of these reading composite skills. In this study, the hypothesis was tested in an adult sample as a model of reading achievement. Participants were parents of children referred for evaluation of reading difficulties. Approximately half of all participants reported difficulty learning to read in childhood and a small subset demonstrated ongoing weaknesses in reading. Structural equation modeling results suggest that the double-deficit hypothesis is an accurate model for understanding adult reading achievement. Better reading achievement was associated with better phonological awareness and faster rapid automatized naming in adults. Posthoc analyses indicated that individuals with double deficits had significantly lower reading achievement than individuals with single deficits or no deficits. 相似文献
129.
We explore the feasibility of automatically identifying sentences in different MEDLINE abstracts that are related in meaning.
We compared traditional vector space models with machine learning methods for detecting relatedness, and found that machine
learning was superior. The Huber method, a variant of Support Vector Machines which minimizes the modified Huber loss function,
achieves 73% precision when the score cutoff is set high enough to identify about one related sentence per abstract on average.
We illustrate how an abstract viewed in PubMed might be modified to present the related sentences found in other abstracts
by this automatic procedure. 相似文献
130.
This article analyses the overall performance of the Peer‐Assisted Student Support (PASS) Scheme in the Business School at the University of Glamorgan. Observations were made over a seven‐week period to measure the effectiveness of the scheme in terms of enhancing the student learning process. Weekly attendance was measured to establish patterns of demand in terms of age, gender and mentored subject area. Further quantitative and qualitative research was undertaken to provide an insight into the perceived benefits of the scheme in relation to student social development and academic performance. The empirical findings of this article show that PASS attendance is female dominated. Moreover, the research suggests that contrary to previous research, the majority of benefactors reside in the under‐21 age group. The findings also highlight that academic and laboratory‐based subjects are a considerable strain on PASS resources and more significantly superior academic performance is positively correlated with regular PASS attendance. 相似文献