

{"id":4,"date":"2011-12-08T11:55:34","date_gmt":"2011-12-08T11:55:34","guid":{"rendered":"http:\/\/project.inria.fr\/template1\/?page_id=4"},"modified":"2026-03-18T14:56:12","modified_gmt":"2026-03-18T13:56:12","slug":"home","status":"publish","type":"page","link":"https:\/\/project.inria.fr\/expand\/","title":{"rendered":"Expand &#8212; Expanding the Reach of Ontology-Based Data Access: EXpressivity, exPlanation and Algorithms"},"content":{"rendered":"<p><\/p>\n\n\n<p>In a data-driven society where decision-making depends on advanced data analysis, valuable information<br \/>is often scattered across multiple sources. Moreover, raw data is rarely available in a directly usable form:<br \/>various transformation operations are required, such as reformatting, changing description vocabulary,<br \/>normalizing units or making inferences to complete information. This raises the challenge of providing an<br \/>integrated view of multiple data sources to allow for intuitive and efficient querying by a stakeholder.<br \/>The EXPAND project aims to facilitate data access and integration through the Ontology-Based Data Access<br \/>(OBDA) technology. In a nutshell, OBDA provides a principled way of integrating multiple data<br \/>sources by adding an ontological layer on top of them. This paradigm has several benefits. First, OBDA<br \/>allows one to unify and enrich data sources by establishing explicit relationships between raw data and<br \/>ontology terms. Second, OBDA enables users to query diverse data repositories using a high-level vocabulary<br \/>provided by the ontology, disregarding the actual data formats, while leveraging logical inference to retrieve<br \/>richer answers than classical evaluation techniques. Third, by providing a unified view of information across<br \/>multiple datasets and inferring missing information, OBDA allows for querying even incomplete databases.<\/p>\n<p>&nbsp;<\/p>\n<p>Expand aims at enriching the current OBDA framework by:<\/p>\n<ol>\n<li>support various query classes well studied and understood in database settings, such as navigational queries, aggregation queries and some very restricted forms of negation;<\/li>\n<li>provide enough context to a user to help<br \/>them to accept or discard answers provided by the system, in particular by leveraging techniques from neighbouring fields (databases, knowledge compilation,&#8230;); we will investigate how to provide explanations and how to explore large answer sets<\/li>\n<li>the development of optimization techniques to make an expressive OBDA framework applicable in practice.<\/li>\n<\/ol>","protected":false},"excerpt":{"rendered":"<p>In a data-driven society where decision-making depends on advanced data analysis, valuable informationis often scattered across multiple sources. Moreover, raw data is rarely available in a directly usable form:various transformation operations are required, such as reformatting, changing description vocabulary,normalizing units or making inferences to complete information. This raises the challenge\u2026<\/p>\n<p> <a class=\"continue-reading-link\" href=\"https:\/\/project.inria.fr\/expand\/\"><span>Continue reading<\/span><i class=\"crycon-right-dir\"><\/i><\/a> <\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"open","template":"","meta":{"footnotes":""},"class_list":["post-4","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/project.inria.fr\/expand\/wp-json\/wp\/v2\/pages\/4","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/project.inria.fr\/expand\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/project.inria.fr\/expand\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/project.inria.fr\/expand\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/project.inria.fr\/expand\/wp-json\/wp\/v2\/comments?post=4"}],"version-history":[{"count":6,"href":"https:\/\/project.inria.fr\/expand\/wp-json\/wp\/v2\/pages\/4\/revisions"}],"predecessor-version":[{"id":120,"href":"https:\/\/project.inria.fr\/expand\/wp-json\/wp\/v2\/pages\/4\/revisions\/120"}],"wp:attachment":[{"href":"https:\/\/project.inria.fr\/expand\/wp-json\/wp\/v2\/media?parent=4"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}