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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Anthony Bigot Claude Chrisment Taoufiq Dkaki Gilles Hubert Josiane Mothe 《Information Retrieval》2011,14(6):617-648
To evaluate Information Retrieval Systems on their effectiveness, evaluation programs such as TREC offer a rigorous methodology
as well as benchmark collections. Whatever the evaluation collection used, effectiveness is generally considered globally,
averaging the results over a set of information needs. As a result, the variability of system performance is hidden as the
similarities and differences from one system to another are averaged. Moreover, the topics on which a given system succeeds
or fails are left unknown. In this paper we propose an approach based on data analysis methods (correspondence analysis and
clustering) to discover correlations between systems and to find trends in topic/system correlations. We show that it is possible
to cluster topics and systems according to system performance on these topics, some system clusters being better on some topics.
Finally, we propose a new method to consider complementary systems as based on their performances which can be applied for
example in the case of repeated queries. We consider the system profile based on the similarity of the set of TREC topics
on which systems achieve similar levels of performance. We show that this method is effective when using the TREC ad hoc collection. 相似文献
992.
Olivier Chapelle Shihao Ji Ciya Liao Emre Velipasaoglu Larry Lai Su-Lin Wu 《Information Retrieval》2011,14(6):572-592
We study the problem of web search result diversification in the case where intent based relevance scores are available. A
diversified search result will hopefully satisfy the information need of user-L.s who may have different intents. In this
context, we first analyze the properties of an intent-based metric, ERR-IA, to measure relevance and diversity altogether.
We argue that this is a better metric than some previously proposed intent aware metrics and show that it has a better correlation
with abandonment rate. We then propose an algorithm to rerank web search results based on optimizing an objective function
corresponding to this metric and evaluate it on shopping related queries. 相似文献
993.
As new media technologies and platforms emerge and take hold in our society, traditional publishers are wondering: What’s in this new content climate for me? The simple answer is: a lot. The digital world, mobile content delivery mechanisms and the public’s increasing comfort—even preference for—a media menu from which they can pick and choose what they want and how they want to receive it, brings exciting and potentially lucrative opportunities. For publishers who understand how to leverage their brand and create authentic, identifiable value in the eyes of the customer, risk can be reduced and new revenue streams built. Here are four best practices to position your publishing company for growth. 相似文献
994.
Christopher Platt 《Publishing Research Quarterly》2011,27(3):247-253
Updated from a presentation given at Biblionext.it in Rome in April 2011, this article will highlight The New York Public
Library’s success with e-books and other forms of popular e-content and our efforts to stay one step ahead of the consumer
shift from print reading to e-reading. Consumer e-reading is dominated by Amazon.com in the US, followed by one of the largest
chain bookstores, BarnesandNoble.com. The availability of digital versions of very popular titles, coupled with the explosion
of e-readers, tablets, and smartphones that are priced competitively and fairly easy to use, are helping move a lot of Americans
into the e-book world. Last month, Amazon.com announced they sold more e-books than physical books for the first time ever.
Print books are not going away, but our experience is that it is clear e-books are no longer just an extra format to offer,
they are integral to our future. 相似文献
995.
Felicitas Kraemer Kees van Overveld Martin Peterson 《Ethics and Information Technology》2011,13(3):251-260
We argue that some algorithms are value-laden, and that two or more persons who accept different value-judgments may have
a rational reason to design such algorithms differently. We exemplify our claim by discussing a set of algorithms used in
medical image analysis: In these algorithms it is often necessary to set certain thresholds for whether e.g. a cell should
count as diseased or not, and the chosen threshold will partly depend on the software designer’s preference between avoiding
false positives and false negatives. This preference ultimately depends on a number of value-judgments. In the last section
of the paper we discuss some general principles for dealing with ethical issues in algorithm-design. 相似文献
996.
Philip J. Nickel 《Ethics and Information Technology》2011,13(4):355-363
In this paper, I examine the ethics of e-trust and e-trustworthiness in the context of health care, looking at direct computer-patient interfaces (DCPIs), information systems that provide medical
information, diagnosis, advice, consenting and/or treatment directly to patients without clinicians as intermediaries. Designers,
manufacturers and deployers of such systems have an ethical obligation to provide evidence of their trustworthiness to users.
My argument for this claim is based on evidentialism about trust and trustworthiness: the idea that trust should be based on sound evidence of trustworthiness. Evidence of trustworthiness
is a broader notion than one might suppose, including not just information about the risks and performance of the system,
but also interactional and context-based information. I suggest some sources of evidence in this broader sense that make it
plausible that designers, manufacturers and deployers of DCPIs can provide evidence to users that is cognitively simple, easy
to communicate, yet rationally connected with actual trustworthiness. 相似文献
997.
998.
Bibliometric mapping of computer and information ethics 总被引:1,自引:0,他引:1
Richard Heersmink Jeroen van den Hoven Nees Jan van Eck Jan van den Berg 《Ethics and Information Technology》2011,13(3):241-249
This paper presents the first bibliometric mapping analysis of the field of computer and information ethics (C&IE). It provides
a map of the relations between 400 key terms in the field. This term map can be used to get an overview of concepts and topics
in the field and to identify relations between information and communication technology concepts on the one hand and ethical
concepts on the other hand. To produce the term map, a data set of over thousand articles published in leading journals and
conference proceedings in the C&IE field was constructed. With the help of various computer algorithms, key terms were identified
in the titles and abstracts of the articles and co-occurrence frequencies of these key terms were calculated. Based on the
co-occurrence frequencies, the term map was constructed. This was done using a computer program called VOSviewer. The term
map provides a visual representation of the C&IE field and, more specifically, of the organization of the field around three
main concepts, namely privacy, ethics, and the Internet. 相似文献
999.
Gordon Hull Heather Richter Lipford Celine Latulipe 《Ethics and Information Technology》2011,13(4):289-302
Social networking sites like Facebook are rapidly gaining in popularity. At the same time, they seem to present significant
privacy issues for their users. We analyze two of Facebooks’s more recent features, Applications and News Feed, from the perspective
enabled by Helen Nissenbaum’s treatment of privacy as “contextual integrity.” Offline, privacy is mediated by highly granular
social contexts. Online contexts, including social networking sites, lack much of this granularity. These contextual gaps
are at the root of many of the sites’ privacy issues. Applications, which nearly invisibly shares not just a users’, but a
user’s friends’ information with third parties, clearly violates standard norms of information flow. News Feed is a more complex
case, because it involves not just questions of privacy, but also of program interface and of the meaning of “friendship”
online. In both cases, many of the privacy issues on Facebook are primarily design issues, which could be ameliorated by an
interface that made the flows of information more transparent to users. 相似文献
1000.
Thomas W. Simpson 《Ethics and Information Technology》2011,13(1):29-38
Trust online can be a hazardous affair; many are trustworthy, but some people use the anonymity of the web to behave very badly indeed. So how can we improve the quality of evidence for trustworthiness provided online? I focus on one of the devices we use to secure others’ trustworthiness: tracking past conduct through online reputation systems. Yet existing reputation systems face problems. I analyse these, and in the light of this develop some principles for system design, towards overcoming these challenges. In providing better evidence for trustworthiness online, so we can also encourage people actually to be trustworthy more often, which is an ethically welcome outcome. 相似文献