174,422 research outputs found
Semantic Query Reformulation in Social PDMS
We consider social peer-to-peer data management systems (PDMS), where each
peer maintains both semantic mappings between its schema and some
acquaintances, and social links with peer friends. In this context,
reformulating a query from a peer's schema into other peer's schemas is a hard
problem, as it may generate as many rewritings as the set of mappings from that
peer to the outside and transitively on, by eventually traversing the entire
network. However, not all the obtained rewritings are relevant to a given
query. In this paper, we address this problem by inspecting semantic mappings
and social links to find only relevant rewritings. We propose a new notion of
'relevance' of a query with respect to a mapping, and, based on this notion, a
new semantic query reformulation approach for social PDMS, which achieves great
accuracy and flexibility. To find rapidly the most interesting mappings, we
combine several techniques: (i) social links are expressed as FOAF (Friend of a
Friend) links to characterize peer's friendship and compact mapping summaries
are used to obtain mapping descriptions; (ii) local semantic views are special
views that contain information about external mappings; and (iii) gossiping
techniques improve the search of relevant mappings. Our experimental
evaluation, based on a prototype on top of PeerSim and a simulated network
demonstrate that our solution yields greater recall, compared to traditional
query translation approaches proposed in the literature.Comment: 29 pages, 8 figures, query rewriting in PDM
Science Models as Value-Added Services for Scholarly Information Systems
The paper introduces scholarly Information Retrieval (IR) as a further
dimension that should be considered in the science modeling debate. The IR use
case is seen as a validation model of the adequacy of science models in
representing and predicting structure and dynamics in science. Particular
conceptualizations of scholarly activity and structures in science are used as
value-added search services to improve retrieval quality: a co-word model
depicting the cognitive structure of a field (used for query expansion), the
Bradford law of information concentration, and a model of co-authorship
networks (both used for re-ranking search results). An evaluation of the
retrieval quality when science model driven services are used turned out that
the models proposed actually provide beneficial effects to retrieval quality.
From an IR perspective, the models studied are therefore verified as expressive
conceptualizations of central phenomena in science. Thus, it could be shown
that the IR perspective can significantly contribute to a better understanding
of scholarly structures and activities.Comment: 26 pages, to appear in Scientometric
Building a terminology network for search: the KoMoHe project
The paper reports about results on the GESIS-IZ project "Competence Center
Modeling and Treatment of Semantic Heterogeneity" (KoMoHe). KoMoHe supervised a
terminology mapping effort, in which 'cross-concordances' between major
controlled vocabularies were organized, created and managed. In this paper we
describe the establishment and implementation of cross-concordances for search
in a digital library (DL).Comment: 5 pages, 2 figure, Dublin Core Conference 200
Applying Science Models for Search
The paper proposes three different kinds of science models as value-added
services that are integrated in the retrieval process to enhance retrieval
quality. The paper discusses the approaches Search Term Recommendation,
Bradfordizing and Author Centrality on a general level and addresses
implementation issues of the models within a real-life retrieval environment.Comment: 14 pages, 3 figures, ISI 201
Cross-concordances: terminology mapping and its effectiveness for information retrieval
The German Federal Ministry for Education and Research funded a major
terminology mapping initiative, which found its conclusion in 2007. The task of
this terminology mapping initiative was to organize, create and manage
'cross-concordances' between controlled vocabularies (thesauri, classification
systems, subject heading lists) centred around the social sciences but quickly
extending to other subject areas. 64 crosswalks with more than 500,000
relations were established. In the final phase of the project, a major
evaluation effort to test and measure the effectiveness of the vocabulary
mappings in an information system environment was conducted. The paper reports
on the cross-concordance work and evaluation results.Comment: 19 pages, 4 figures, 11 tables, IFLA conference 200
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