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1.
Measuring Search Engine Quality   总被引:12,自引:3,他引:9  
The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures.  相似文献   
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The Copyright Licensing and Administration Society of Singapore was established in 1999. It is now profitable and commercially significant, perhaps uniquely so in Asia. Critical factors in its growth have included a statutory (non‐voluntary) photocopying licence provision for educational institutions in the Copyright Act; and widespread support from the local and international communities of rightsholders. Tentative consensus has been established with educators over a fair level of remuneration for copying. Further work needs to be done to extend or amend the current model for electronic copying, for the private sector and for other countries in the region.  相似文献   
5.
During the rewriting of its program in the early 1980s, theRassemblement pour la République (RPR) carried out anumber of opinion surveys. The person in charge of this wasnot a member of the inner leadership circle; he warned the partyleader, Jacques Chirac, that themes forming a coherent ‘liberal’program for the transformation of the relationship between citizens,state, and the economy, were not popular with public opinion,which remained attached to progressive taxation and a comprehensivesocial welfare system. The party leadership ignored these warnings.Rather than attempting to align their policies with voter aspirations,their principal use of political communications techniques aimedat improving their leader's image. The person in charge of thiswork was a stranger to politics whose understanding of the waycultural or political attitudes are changed led him to interpretvery fatalistically the chances of influencing election outcomesby communications techniques. His methods were treated withfrank skepticism by party communications colleagues, his client'spersonality was particularly unamenable to his efforts, andhis one successful initiative—the rejuvenation of theexecutive committee—was operated at the cost of a rowin the party. In the case of the RPR, opinion research seemsto have played no role at all in an important party policy review,the causes of which should be sought elsewhere.  相似文献   
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Conclusions Palestinian teachers at the pre-collegiate level who participate in the CEEPAT programme will, it is hoped, learn to place new emphasis on enhancement of their students' analytical skills and discourage an identification of knowledge with memorisation. For their part, Palestinian professors who have been trained to teach in the programme will presumably constitute a growing reservoir of talent which may be expected to raise the quality of Palestinian university education. Plans are now under way to give all Palestinians teaching under the auspices of CEEPAT an opportunity to attend an annual, three-week winter seminar in Gaza and/or a summer seminar in the United States, both of which will focus on issues of pedagogy and methodology. Such professors can be expected to pass on their new understanding of teaching via discussion to their colleagues and to their university students, thereby spreading an important pedagogical method to other segments of the Palestinian... community. 7 CEEPAT clearly has the potential to make a significant contribution to the elevation of educational standards in Palestine at a time of major historical change.In Palestine, higher education of quality is obviously a very serious business. It is understood that it underlies any possibility of individual betterment, economic development, or the evolution of an independent Palestinian state. If ever the Israeli occupation is completely terminated and the present financial crisis of the universities is solved, Palestinian university and post-baccalaureate training may reasonably be expected to become fully competitive on an international scale.  相似文献   
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Book reviews     
cAbd al‐Malik b. Habib. Kitāb al‐Ta'rij (La historia). Edición y estudio por Jorge Aguadé. Madrid: Consejo Superior de Investigaciones Científicas & Instituto de Cooperación con el Mundo Arabe, 1991 (Fuentes Arabico‐Hispanas, 1). 163 + 224 pp. [Arabic title: Kltāb al‐Ta'tikh]

Kedar, Benjamin Z., ed. The Horns of Hattin. Jerusalem and London: Yad Izhak Ben‐Zvi, Israel Exploration Society and Variorum 1992. 368 pp., 12 plates; $74.75 (cloth).

Köprülü, Mehmed Fuad. The Seljuks of Anatolia: Their History and Culture According to Local Muslim Sources. Translated and edited by Gary Leiser. Salt Lake City: University of Utah, 1992. xi +101 pp., $22.00 (cloth).

Cameron, Averil and Conrad, Lawrence I., eds. The Byzantine and Early Islamic Near East: Problems in the Literary Source Material (Papers in the First Workshop on Late Antiquity and Early Islam). Princeton: The Darwin Press, 1992. xiv + 428pp., 12 plates; $29.25 (cloth).

Vereno, Ingolf. Studien zum ältesten alchemistischen Schrifttum. Berlin: Klaus Schwarz Verlag, 1992 (Islamkundliche Untersuchungen, 155). 414pp.

Tolan, John. Petrus Alfonsi and his Medieval Readers. Gainesville, Florida: University Press of Florida, 1993. xv + 288pp., $34.95 (cloth), $16.95 (paper).

Lassner, Jacob. Demonizing the Queen of Sheba: Boundaries of Gender and Culture in Postbiblical Judaism and Medieval Islam. Chicago: University of Chicago, 1994. 281 pp., $19.95 (paper), $49.95 (cloth).

Menocal, María Rosa. Shards of Love: Exile and the Origins of the Lyric. Durham, North Carolina: Duke University Press, 1994. xv + 295pp., $34.95 (cloth), $14.95 (paper).

Massignon, Louis. The Passion of al‐Hallāj, Mystic and Martyr of Islam. Translated and edited by Herbert Mason. Abridged edition, Bollingen Series XCVIII. Princeton: Princeton University Press, 1994. xxxi + 293pp.

Viguera Molins, Maria Jesús. El Islam en Aragón. Saragossa: Caja de Ahorros de la Inmaculada, 1995 (Colección “Mariano de Pano y Ruata”, 9), 174 pp., 182 ills. in colour, maps, diagrams, charts etc No price stated.  相似文献   

8.
In 1991, the Reference and Information Services staff of the Alfred Taubman Medical Library at the University of Michigan gathered data on the use of the reference desk, including the frequency and types of assistance requested by different user groups throughout the year. Recommendations based on the results of this study led to improved service as well as more efficient use of staff resources.  相似文献   
9.
There is growing research on voting behavior in referendums.However, the dynamics of opinion formation in popular referendums,referendums initiated by the electorate to approve or rejectdecisions made by representative bodies, has not yet been studied.This is especially unfortunate as voting decisions in popularreferendums differ from those in other referendums in interestingways. Opinion formation can be a very dynamic process in popularreferendums, making the referendum campaign crucial. This paperstudies the dynamics of opinion formation in popular referendumsand relates them to particular characteristics of the campaignsand the issues at hand. Based on the literature, we consideredthe effects of the intensity of the yes and no campaigns, familiaritywith the issue, and partisan cues. Our study uses content analysisdata and data from public opinion surveys dealing with variouspopular referendums held in the Netherlands. The study revealedseveral factors that contributed to the volatility of opinionsin the referendum campaigns: the issue (new and did not fittraditional political schemes), lack of support from societaland community organizations for the position of the local authorities,and low profile campaigns on the part of local authorities.While some of these factors are general and may play a rolein referendums everywhere, some can be considered ‘typicallyDutch’, related to the characteristics of popular referendumsin the Netherlands and the country’s political system.  相似文献   
10.
The benefits claimed for open access publishing in the medical area are subjected to evaluation and question. It is represented that these benefits are, in many cases, illusory or doubtful.  相似文献   
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