Mapping queries to the Linking Open Data cloud: A case study using DBpedia.

a b s t r a c t We introduce the task of mapping search engine queries to DBpedia, a major linking hub in the Linking Open Data cloud. We propose and compare various methods for addressing this task, using a mixture of information retrieval and machine learning techniques. Specifically, we present a supervised machine learning-based method to determine which concepts are intended by a user issuing a query. The concepts are obtained from an ontology and may be used to provide contextual information, related concepts, or navigational suggestions to the user submitting the query. Our approach first ranks candidate concepts using a language modeling for information retrieval framework. We then extract query, concept, and search-history feature vectors for these concepts. Using manual annotations we inform a machine learning algorithm that learns how to select concepts from the candidates given an input query. Simply performing a lexical match between the queries and concepts is found to perform poorly and so does using retrieval alone, i.e., omitting the concept selection stage. Our proposed method significantly improves upon these baselines and we find that support vector machines are able to achieve the best performance out of the machine learning algorithms evaluated

Linked Data Supported Information Retrieval

Um Inhalte im World Wide Web ausfindig zu machen, sind Suchmaschienen nicht mehr wegzudenken. Semantic Web und Linked Data Technologien ermöglichen ein detaillierteres und eindeutiges Strukturieren der Inhalte und erlauben vollkommen neue Herangehensweisen an die Lösung von Information Retrieval Problemen. Diese Arbeit befasst sich mit den Möglichkeiten, wie Information Retrieval Anwendungen von der Einbeziehung von Linked Data profitieren können. Neue Methoden der computer-gestützten semantischen Textanalyse, semantischen Suche, Informationspriorisierung und -visualisierung werden vorgestellt und umfassend evaluiert. Dabei werden Linked Data Ressourcen und ihre Beziehungen in die Verfahren integriert, um eine Steigerung der Effektivität der Verfahren bzw. ihrer Benutzerfreundlichkeit zu erzielen. Zunächst wird eine Einführung in die Grundlagen des Information Retrieval und Linked Data gegeben. Anschließend werden neue manuelle und automatisierte Verfahren zum semantischen Annotieren von Dokumenten durch deren Verknüpfung mit Linked Data Ressourcen vorgestellt (Entity Linking). Eine umfassende Evaluation der Verfahren wird durchgeführt und das zu Grunde liegende Evaluationssystem umfangreich verbessert. Aufbauend auf den Annotationsverfahren werden zwei neue Retrievalmodelle zur semantischen Suche vorgestellt und evaluiert. Die Verfahren basieren auf dem generalisierten Vektorraummodell und beziehen die semantische Ähnlichkeit anhand von taxonomie-basierten Beziehungen der Linked Data Ressourcen in Dokumenten und Suchanfragen in die Berechnung der Suchergebnisrangfolge ein. Mit dem Ziel die Berechnung von semantischer Ähnlichkeit weiter zu verfeinern, wird ein Verfahren zur Priorisierung von Linked Data Ressourcen vorgestellt und evaluiert. Darauf aufbauend werden Visualisierungstechniken aufgezeigt mit dem Ziel, die Explorierbarkeit und Navigierbarkeit innerhalb eines semantisch annotierten Dokumentenkorpus zu verbessern. Hierfür werden zwei Anwendungen präsentiert. Zum einen eine Linked Data basierte explorative Erweiterung als Ergänzung zu einer traditionellen schlüsselwort-basierten Suchmaschine, zum anderen ein Linked Data basiertes Empfehlungssystem

Legal crowdsourcing and relational law : what the semantic web can do for legal education

Crowdsourcing and Relational Law are interrelated concepts that can be successfully applied to the legal domain and, more specifically, to the field of legal education. 'Crowdsourcing' means 'participation of people (crowds)' and refers theoretically to the aggregated production of a common knowledge in a global data space. 'Relational law' refers to the regulatory link between Web 2.0 and 3.0, based on trust and dialogue, which emerges from the intertwining of top-down existing legal systems and bottom-up participation (the Web of People). Legal education today has a major role to play in the broad space opened up in terms of future potential of the Semantic Web. The following paper places a lens on the educational value of crowdsourcing and the relational approach to governance and law

Traductor de consultas SPARQL, formuladas sobre fuentes de datos incompletamente alineadas, que aporta una estimación de la calidad de la traducción.

147 p.Hoy en día existe en la Web un número cada vez mayor de conjuntos de datos enlazados de distinta procedencia, referentes a diferentes dominios y que se encuentran accesibles al público en general para ser libremente explotados. Esta tesis doctoral centra su estudio en el ámbito del procesamiento de consultas sobre dicha nube de conjuntos de datos enlazados, abordando las dificultades en su acceso por aspectos relacionados con su heterogeneidad. La principal contribución reside en el planteamiento de una nueva propuesta que permite traducir la consulta realizada sobre un conjunto de datos enlazado a otro sin que estos se encuentren completamente alineados y sin que el usuario tenga que conocer las características técnicas inherentes a cada fuente de datos. Esta propuesta se materializa en un traductor que transforma una consulta SPARQL, adecuadamente expresada en términos de los vocabularios utilizados en un conjunto de datos de origen, en otra consulta SPARQL adecuadamente expresada para un conjunto de datos objetivo que involucra diferentes vocabularios. La traducción se basa en alineaciones existentes entre términos en diferentes conjuntos de datos. Cuando el traductor no puede producir una consulta semánticamente equivalente debido a la escasez de alineaciones de términos, elsistema produce una aproximación semántica de la consulta para evitar devolver una respuesta vacía al usuario. La traducción a través de los distintos conjuntos de datos se logra gracias a la aplicación de un variado grupo de reglas de transformación. En esta tesis se han definido cinco tipos de reglas, dependiendo de la motivación de la transformación, que son: equivalencia, jerarquía, basadas en las respuestas de la consulta, basadas en el perfil de los recursos que aparecen en la consulta y basadas en las características asociadas a los recursos que aparecen en la consulta.Además, al no garantizar el traductor la preservación semántica debido a la heterogeneidad de los vocabularios se vuelve crucial el obtener una estimación de la calidad de la traducción producida. Por ello otra de las contribuciones relevantes de la tesis consiste en la definición del modo en que informar al usuario sobre la calidad de la consulta traducida, a través de dos indicadores: un factor de similaridad que se basa en el proceso de traducción en sí, y un indicador de calidad de los resultados, estimado gracias a un modelo predictivo.Finalmente, esta tesis aporta una demostración de la viabilidad estableciendo un marco de evaluación sobre el que se ha validado un prototipo del sistema

Interaction Design and User Needs for TV Broadcasts Enriched with Linked Open Data

Increasingly, people are consuming television content on devices connected to the Internet that allow them to look up related information. In parallel, Europe is publishing growing amounts of Linked Open Data, including rich metadata about its cultural heritage. The goal of the LinkedTV project is to seamlessly interlink TV and Web content to enrich the user’s experience of both. Linked Data and semantic technologies enable broadcasters to achieve added value for their content at low cost through the re-use of existing metadata. We present two user studies related to different user scenarios: Interactive News and Hyperlinked Documentary). These studies reveal the different user requirements and infor

Audio-Visual Semantics: propuesta de una ontología para la descripción de secuencias audiovisuales

This paper shows the description of the conceptual aspects of audiovisual content through the Audio-Visual Semantics ontology (AVS) that allows to represent actions, characteristics and interactions between entities and / or elements with a multilevel granularity. For this, it is considered that the audiovisual pieces are composed of sequences. In these sequences it is possible to identify different happenings that can be described. Happenings are composed of a series of elements such as agents, actions, targets or other events. The use of qualifiers (specifying their scope and value) is contemplated to define qualities or attributes of the different elements that intervene in an event. The agents, actions, objects and qualifiers are not defined extensively in the ontology itself, but are referenced as concepts of SKOS vocabularies, which avoids modifying the AVS ontology and allows to define semantic relations between concepts and multilingual labeling. Currently, the AVS ontology is in development and in the validation phase through the description of audiovisual pieces and the verification of the results obtained

Deliverable D4.1 Specification of user profiling and contextualisation

This deliverable presents a comprehensive research of past work in the field of capturing and interpreting user preferences and context and an overview of relevant digital media-specific techniques, aiming to provide insights and ideas for innovative context-aware user preference learning and to justify the user modelling strategies considered within LinkedTV’s WP4. Based on this research and a study over the specific technical and conceptual requirements of LinkedTV, a prototypical design for profiling and contextualizing user needs in a linked media environment is specified

Audio-Visual Semantics: propuesta de una ontología para la descripción de secuencias audiovisuales

This paper shows the description of the conceptual aspects of audiovisual content through the Audio-Visual Semantics ontology (AVS) that allows to represent actions, characteristics and interactions between entities and / or elements with a multilevel granularity. For this, it is considered that the audiovisual pieces are composed of sequences. In these sequences it is possible to identify different happenings that can be described. Happenings are composed of a series of elements such as agents, actions, targets or other events. The use of qualifiers (specifying their scope and value) is contemplated to define qualities or attributes of the different elements that intervene in an event. The agents, actions, objects and qualifiers are not defined extensively in the ontology itself, but are referenced as concepts of SKOS vocabularies, which avoids modifying the AVS ontology and allows to define semantic relations between concepts and multilingual labeling. Currently, the AVS ontology is in development and in the validation phase through the description of audiovisual pieces and the verification of the results obtained

Development of linguistic linked open data resources for collaborative data-intensive research in the language sciences

Making diverse data in linguistics and the language sciences open, distributed, and accessible: perspectives from language/language acquistiion researchers and technical LOD (linked open data) researchers. This volume examines the challenges inherent in making diverse data in linguistics and the language sciences open, distributed, integrated, and accessible, thus fostering wide data sharing and collaboration. It is unique in integrating the perspectives of language researchers and technical LOD (linked open data) researchers. Reporting on both active research needs in the field of language acquisition and technical advances in the development of data interoperability, the book demonstrates the advantages of an international infrastructure for scholarship in the field of language sciences. With contributions by researchers who produce complex data content and scholars involved in both the technology and the conceptual foundations of LLOD (linguistics linked open data), the book focuses on the area of language acquisition because it involves complex and diverse data sets, cross-linguistic analyses, and urgent collaborative research. The contributors discuss a variety of research methods, resources, and infrastructures. Contributors Isabelle Barrière, Nan Bernstein Ratner, Steven Bird, Maria Blume, Ted Caldwell, Christian Chiarcos, Cristina Dye, Suzanne Flynn, Claire Foley, Nancy Ide, Carissa Kang, D. Terence Langendoen, Barbara Lust, Brian MacWhinney, Jonathan Masci, Steven Moran, Antonio Pareja-Lora, Jim Reidy, Oya Y. Rieger, Gary F. Simons, Thorsten Trippel, Kara Warburton, Sue Ellen Wright, Claus Zin