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Tuomo Korenius Jorma Laurikkala Martti Juhola Kalervo Järvelin 《Information Retrieval》2006,9(1):33-53
Search facilitated with agglomerative hierarchical clustering methods was studied in a collection of Finnish newspaper articles
(N = 53,893). To allow quick experiments, clustering was applied to a sample (N = 5,000) that was reduced with principal components analysis. The dendrograms were heuristically cut to find an optimal partition,
whose clusters were compared with each of the 30 queries to retrieve the best-matching cluster. The four-level relevance assessment
was collapsed into a binary one by (A) considering all the relevant and (B) only the highly relevant documents relevant, respectively.
Single linkage (SL) was the worst method. It created many tiny clusters, and, consequently, searches enabled with it had high
precision and low recall. The complete linkage (CL), average linkage (AL), and Ward's methods (WM) returned reasonably-sized
clusters typically of 18–32 documents. Their recall (A: 27–52%, B: 50–82%) and precision (A: 83–90%, B: 18–21%) was higher
than and comparable to those of the SL clusters, respectively. The AL and WM clustering had 1–8% better effectiveness than
nearest neighbor searching (NN), and SL and CL were 1–9% less efficient that NN. However, the differences were statistically
insignificant. When evaluated with the liberal assessment A, the results suggest that the AL and WM clustering offer better
retrieval ability than NN. Assessment B renders the AL and WM clustering better than NN, when recall is considered more important
than precision. The results imply that collections in the highly inflectional and agglutinative languages, such as Finnish,
may be clustered as the collections in English, provided that documents are appropriately preprocessed. 相似文献
146.
Searching online information resources using mobile devices is affected by small screens which can display only a fraction
of ranked search results. In this paper we investigate whether the search effort can be reduced by means of a simple user
feedback: for a screenful of search results the user is encouraged to indicate a single most relevant document. In our approach
we exploit the fact that, for small display sizes and limited user actions, we can construct a user decision tree representing
all possible outcomes of the user interaction with the system. Examining the trees we can compute an upper limit on relevance
feedback performance. In this study we consider three standard feedback algorithms: Rocchio, Robertson/Sparck-Jones (RSJ)
and a Bayesian algorithm. We evaluate them in conjunction with two strategies for presenting search results: a document ranking
that attempts to maximize information gain from the user’s choices and the top-D ranked documents. Experimental results indicate
that for RSJ feedback which involves an explicit feature selection policy, the greedy top-D display is more appropriate. For
the other two algorithms, the exploratory display that maximizes information gain produces better results. We conducted a
user study to compare the performance of the relevance feedback methods with real users and compare the results with the findings
from the tree analysis. This comparison between the simulations and real user behaviour indicates that the Bayesian algorithm,
coupled with the sampled display, is the most effective.
Extended version of “Evaluating Relevance Feedback Algorithms for Searching on Small Displays, ” Vishwa Vinay, Ingemar J.
Cox, Natasa Milic-Frayling, Ken Wood published in the proceedings of ECIR 2005, David E. Losada, Juan M. Fernández-Luna (Eds.),
Springer 2005, ISBN 3-540-25295-9 相似文献
147.
石峰:发展数字报业,传统媒体是基础
"十一五"期间是我国报业出版业深化改革加快发展的关键时期,为了迎接报业的挑战,抓住数字内容产业蓬勃发展的历史机遇,新闻出版总署提出大力发展数字报业的战略目标,并为此制订了专门的行动计划,即中国数字报业实验室计划.旨在全行业广泛联合相关的产业,共同推进我国报业面向未来的战略转型,进一步巩固和加强党的宣传舆论阵地,牢牢把握信息传播技术条件下,新闻宣传和传播市场的主导作用. 相似文献
148.
Toyo Yoshizaki 《Publishing Research Quarterly》2004,19(4):31-36
Summary Now more than ever good translations are proving to be vitally important to fulfilling Shoichi Noma’s mission of advancing
good relationships between cultures. With the emergence of dozens of world-class Japanese writers, the translators of Japanese
literature have acquired a new significance and a new importance. No longer are they required to simply handle the language
like an exotic and precious commodity but they must prepare a writer’s work to compete with literature from around the globe
and let others understand the issues at their very heart of the Japanese people.
Indeed, the selection committee’s choice of Murakami’s Wind-Up Bird Chronicle is an apt example of how literature at its very best can span cultural divides to promote mutual understanding of very complicated
and important world issues. Written for Japanese to help them understand the devastation of war, it is a rare and timely book
that confronts Japan’s experience head on. Ironically, Noma’s idea that books are silent ambassadors, an idea born from agony
and defeat, so many years later is helping the world come together towards a unified vision of peace and understanding.
“Literature has been described as a means of exchange between the hearts of people. Literary translation, then, is the building
of bridges so that all peoples of the world can interact in this way.”
Ye Weiqu, Chinese Institute of Social Studies. 相似文献
149.
150.
Julie J McGowan J Marc Overhage Mike Barnes Clement J McDonald 《Journal of the Medical Library Association》2004,92(2):179-187
In 2001, the Regenstrief Institute for Health Care and the Indiana University School of Medicine (IUSM) began an IAIMS planning effort to create a vision and a tactical plan for the first Integrated Advanced Information Management Systems (IAIMS) implementation to cross a large area and include unaffiliated institutions. A number of elements made this planning effort unique. Among these elements were the existence of a network infrastructure that supported the Indianapolis Network for Patient Care, the existence of a mature medical informatics program at the Regenstrief Institute, and the existence of a wide-area knowledge network fostered by the IUSM libraries. However, the leadership for a strong information technology role in the IUSM that could promote collaboration in support of education and research across the diverse Indianapolis hospital systems had been lacking. By bringing together various groups, each with a commitment to improve health care quality and public health across the Indianapolis metropolitan area, regardless of individual institutional affiliation, the strategic directions for I3-Indianapolis IAIMS Initiative have been defined and the foundations for a third generation IAIMS construct have been laid in Indianapolis, Indiana. 相似文献