共查询到20条相似文献,搜索用时 31 毫秒
1.
Diego Reforgiato Recupero 《Information Retrieval》2007,10(6):563-579
Text document clustering provides an effective and intuitive navigation mechanism to organize a large amount of retrieval
results by grouping documents in a small number of meaningful classes. Many well-known methods of text clustering make use
of a long list of words as vector space which is often unsatisfactory for a couple of reasons: first, it keeps the dimensionality
of the data very high, and second, it ignores important relationships between terms like synonyms or antonyms. Our unsupervised
method solves both problems by using ANNIE and WordNet lexical categories and WordNet ontology in order to create a well structured
document vector space whose low dimensionality allows common clustering algorithms to perform well. For the clustering step
we have chosen the bisecting k-means and the Multipole tree, a modified version of the Antipole tree data structure for, respectively, their accuracy and
speed.
相似文献
Diego Reforgiato RecuperoEmail: |
2.
Evaluation is a major driving force in advancing the state of the art in language technologies. In particular, methods for automatically assessing the quality of machine output is the preferred method for measuring progress, provided that these metrics have been validated against human judgments. Following recent developments in the automatic evaluation of machine translation and document summarization, we present a similar approach, implemented in a measure called POURPRE, an automatic technique for evaluating answers to complex questions based on n-gram co-occurrences between machine output and a human-generated answer key. Until now, the only way to assess the correctness of answers to such questions involves manual determination of whether an information “nugget” appears in a system's response. The lack of automatic methods for scoring system output is an impediment to progress in the field, which we address with this work. Experiments with the TREC 2003, TREC 2004, and TREC 2005 QA tracks indicate that rankings produced by our metric correlate highly with official rankings, and that POURPRE outperforms direct application of existing metrics.
相似文献
Dina Demner-FushmanEmail: |
3.
On information retrieval metrics designed for evaluation with incomplete relevance assessments 总被引:1,自引:0,他引:1
Modern information retrieval (IR) test collections have grown in size, but the available manpower for relevance assessments
has more or less remained constant. Hence, how to reliably evaluate and compare IR systems using incomplete relevance data, where many documents exist that were never examined by the relevance assessors, is receiving a lot of attention.
This article compares the robustness of IR metrics to incomplete relevance assessments, using four different sets of graded-relevance
test collections with submitted runs—the TREC 2003 and 2004 robust track data and the NTCIR-6 Japanese and Chinese IR data
from the crosslingual task. Following previous work, we artificially reduce the original relevance data to simulate IR evaluation
environments with extremely incomplete relevance data. We then investigate the effect of this reduction on discriminative power, which we define as the proportion of system pairs with a statistically significant difference for a given probability of
Type I Error, and on Kendall’s rank correlation, which reflects the overall resemblance of two system rankings according to two different metrics or two different relevance
data sets. According to these experiments, Q′, nDCG′ and AP′ proposed by Sakai are superior to bpref proposed by Buckley and
Voorhees and to Rank-Biased Precision proposed by Moffat and Zobel. We also point out some weaknesses of bpref and Rank-Biased
Precision by examining their formal definitions.
相似文献
Noriko KandoEmail: |
4.
To put an end to the large copyright trade deficit, both Chinese government agencies and publishing houses have been striving
for entering the international publication market. The article analyzes the background of the going-global strategy, and sums
up the performance of both Chinese administrations and publishers.
相似文献
Qing Fang (Corresponding author)Email: |
5.
Jacob Soll 《Archival Science》2007,7(4):331-342
This article examines the archival methods developed by Colbert to train his son in state administration. Based on Colbert’s
correspondence with his son, it reveals the practices Colbert thought necessary to collect and manage information in his state
encyclopedic archive during the last half of the 17th century.
相似文献
Jacob SollEmail: |
6.
Panagiotis Symeonidis Alexandros Nanopoulos Apostolos N. Papadopoulos Yannis Manolopoulos 《Information Retrieval》2008,11(1):51-75
Collaborative Filtering (CF) Systems have been studied extensively for more than a decade to confront the “information overload”
problem. Nearest-neighbor CF is based either on similarities between users or between items, to form a neighborhood of users
or items, respectively. Recent research has tried to combine the two aforementioned approaches to improve effectiveness. Traditional
clustering approaches (k-means or hierarchical clustering) has been also used to speed up the recommendation process. In this paper, we use biclustering
to disclose this duality between users and items, by grouping them in both dimensions simultaneously. We propose a novel nearest-biclusters
algorithm, which uses a new similarity measure that achieves partial matching of users’ preferences. We apply nearest-biclusters
in combination with two different types of biclustering algorithms—Bimax and xMotif—for constant and coherent biclustering,
respectively. Extensive performance evaluation results in three real-life data sets are provided, which show that the proposed
method improves substantially the performance of the CF process.
相似文献
Yannis ManolopoulosEmail: |
7.
Oren Kurland 《Information Retrieval》2009,12(4):437-460
To obtain high precision at top ranks by a search performed in response to a query, researchers have proposed a cluster-based
re-ranking paradigm: clustering an initial list of documents that are the most highly ranked by some initial search, and using
information induced from these (often called) query-specific clusters for re-ranking the list. However, results concerning the effectiveness of various automatic cluster-based re-ranking methods have been inconclusive. We show that using query-specific clusters for automatic re-ranking
of top-retrieved documents is effective with several methods in which clusters play different roles, among which is the smoothing of document language models. We do so by adapting previously-proposed cluster-based retrieval approaches, which are based on (static) query-independent
clusters for ranking all documents in a corpus, to the re-ranking setting wherein clusters are query-specific. The best performing
method that we develop outperforms both the initial document-based ranking and some previously proposed cluster-based re-ranking
approaches; furthermore, this algorithm consistently outperforms a state-of-the-art pseudo-feedback-based approach. In further
exploration we study the performance of cluster-based smoothing methods for re-ranking with various (soft and hard) clustering
algorithms, and demonstrate the importance of clusters in providing context from the initial list through a comparison to
using single documents to this end.
相似文献
Oren KurlandEmail: |
8.
Andy Weissberg 《Publishing Research Quarterly》2008,24(4):255-260
This article analyzes current industry practices toward the identification of digital book content. It highlights key technology
trends, workflow considerations and supply chain behaviors, and examines the implications of these trends and behaviors on
the production, discoverability, purchasing and consumption of digital book products.
相似文献
Andy WeissbergEmail: |
9.
Sandeep Chaufla 《Publishing Research Quarterly》2008,24(3):187-201
A review and analysis of the rules and regulations including the tax aspects of making an investment in India is presented.
The full range from Foreign Direct Investment to different forms of doing business with specific examples from the publishing
industry is explored to help understand current policies and regulations.
相似文献
Sandeep ChauflaEmail: Email: |
10.
A summary overview of the children’s and young adult publishing industry in China with a focus on the size of the market,
ten major publishing houses, copyright and trends. Special emphasis has been placed on specific transaction for the sale of
translation rights from German language publishers to China and minimal activities of German rights sold to Chinese publishers.
相似文献
Jing BartzEmail: |
11.
Participatory archive: towards decentralised curation,radical user orientation,and broader contextualisation of records management 总被引:2,自引:2,他引:0
Isto Huvila 《Archival Science》2008,8(1):15-36
User perspective and user studies have received noticeably little practical attention in archives and archival science. The
purpose of this article is to address the issues of communication and user participation in archival contexts. Two action
research projects-based digital archives are discussed. The insights gained during the research and development work are used
to formulate a new approach to a participatory archive. In spite of the historical nature of the archives discussed, the suggested ways of interacting with an archive are not specific
to historical records. The fundamental characteristics of the proposed approach are decentralised curation, radical user orientation,
and contextualisation of both records and the entire archival process.
相似文献
Isto HuvilaEmail: |
12.
13.
On knowledge-poor methods for person name matching and lemmatization for highly inflectional languages 总被引:1,自引:1,他引:0
Web person search is one of the most common activities of Internet users. Recently, a vast amount of work on applying various
NLP techniques for person name disambiguation in large web document collections has been reported, where the main focus was
on English and few other major languages. This article reports on knowledge-poor methods for tackling person name matching
and lemmatization in Polish, a highly inflectional language with complex person name declension paradigm. These methods apply
mainly well-established string distance metrics, some new variants thereof, automatically acquired simple suffix-based lemmatization
patterns and some combinations of the aforementioned techniques. Furthermore, we also carried out some initial experiments
on deploying techniques that utilize the context, in which person names appear. Results of numerous experiments are presented.
The evaluation carried out on a data set extracted from a corpus of on-line news articles revealed that achieving lemmatization
accuracy figures greater than 90% seems to be difficult, whereas combining string distance metrics with suffix-based patterns
results in 97.6–99% accuracy for the name matching task. Interestingly, no significant additional gain could be achieved through
integrating some basic techniques, which try to exploit the local context the names appear in. Although our explorations were
focused on Polish, we believe that the work presented in this article constitutes practical guidelines for tackling the same
problem for other highly inflectional languages with similar phenomena.
相似文献
Marcin SydowEmail: |
14.
This article concentrates on the retro-archiving of older digital research data. The ADA approach was developed and used to retro-archive older data files, most of which were between 10 and 30 years old. The origin and
main characteristics of the ADA approach are described in the second section of the article. The third section discusses two
recent data-archiving pilot projects that were conducted in the Netherlands. The first of these projects, the ADA project,
laid the foundation for the ADA approach, which was subsequently applied and tested again in the second project, eDNA, which focused on archaeological data. The final section of the article provides a comparison of the results of these
two projects.
相似文献
Heiko TjalsmaEmail: |
15.
A comparison of analyses of the Scottish publishing industry carried out in 1992, 2002 and 2007 underscores the fragility
of the sector within a small country within the English-language community. A number of indices reveal either stability or
stagnation and the picture emerges of the remarkable tenacity of publishing in Scotland. Although there is already a significant
and vital element of state support for publishing in Scotland, further intervention will be necessary to ensure fulfilment
of its potential.
相似文献
Alistair McCleeryEmail: |
16.
17.
Nathan Hollier 《Publishing Research Quarterly》2008,24(3):165-174
This article provides a summary of and commentary on ‘A Lovely Kind of Madness: Small and Independent Publishing in Australia’,
an unpublished report by Kate Freeth, commissioned by the Small Press Underground Networking Community (SPUNC), the representative
body for small and independent publishers in Australia, and released in November 2007. Freeth’s 14,000 word report constitutes
the most detailed and comprehensive study of Australian small and independent publishing since the second volume of Michael
Denholm’s Small Press Publishing in Australia (1991) and provides much primary material for policy makers, scholars, and people working in and around the publishing industry.
相似文献
Nathan HollierEmail: |
18.
On rank-based effectiveness measures and optimization 总被引:1,自引:0,他引:1
Many current retrieval models and scoring functions contain free parameters which need to be set—ideally, optimized. The process
of optimization normally involves some training corpus of the usual document-query-relevance judgement type, and some choice
of measure that is to be optimized. The paper proposes a way to think about the process of exploring the space of parameter
values, and how moving around in this space might be expected to affect different measures. One result, concerning local optima,
is demonstrated for a range of rank-based evaluation measures.
相似文献
Hugo ZaragozaEmail: |
19.
Smoothing of document language models is critical in language modeling approaches to information retrieval. In this paper,
we present a novel way of smoothing document language models based on propagating term counts probabilistically in a graph
of documents. A key difference between our approach and previous approaches is that our smoothing algorithm can iteratively
propagate counts and achieve smoothing with remotely related documents. Evaluation results on several TREC data sets show that the proposed method significantly outperforms the
simple collection-based smoothing method. Compared with those other smoothing methods that also exploit local corpus structures,
our method is especially effective in improving precision in top-ranked documents through “filling in” missing query terms
in relevant documents, which is attractive since most users only pay attention to the top-ranked documents in search engine
applications.
相似文献
ChengXiang ZhaiEmail: |
20.
We present software that generates phrase-based concordances in real-time based on Internet searching. When a user enters
a string of words for which he wants to find concordances, the system sends this string as a query to a search engine and
obtains search results for the string. The concordances are extracted by performing statistical analysis on search results
and then fed back to the user. Unlike existing tools, this concordance consultation tool is language-independent, so concordances
can be obtained even in a language for which there are no well-established analytical methods. Our evaluation has revealed
that concordances can be obtained more effectively than by only using a search engine directly.
相似文献
Yuichiro IshiiEmail: |