Arlind Kopliku

Learn More
Not only SQL (NoSQL) databases are becoming increasingly popular and have some interesting strengths such as scalability and flexibility. In this paper, we investigate on the use of NoSQL systems for implementing OLAP (On-Line Analytical Processing) systems. More precisely, we are interested in instantiating OLAP systems (from the conceptual level to the(More)
In this paper, we propose an attribute retrieval approach which extracts and ranks attributes from HTML tables. We distinguish between class attribute retrieval and instance attribute retrieval. On one hand, given an instance (e.g. University of Strathclyde) we retrieve from the Web its attributes (e.g. principal, location, number of students). On the other(More)
—The plethora of data warehouse solutions has created a need comparing these solutions using experimental benchmarks. Existing benchmarks rely mostly on the relational data model and do not take into account other models. In this paper, we propose an extension to a popular benchmark (the Star Schema Benchmark or SSB) that considers non-relational NoSQL(More)
In this paper we propose an attribute retrieval approach which extracts and ranks attributes from Web tables. We combine simple heuristics to filter out improbable attributes and we rank attributes based on frequencies and a table match score. Ranking is reinforced with external evidence from Web search, DBPedia and Wikipedia. Our approach can be applied to(More)
In this paper, we propose an attribute retrieval approach which extracts and ranks attributes from HTML tables. Given an instance (e.g. Tower of Pisa), we want to retrieve from the Web its attributes (e.g. height, architect). Our approach uses HTML tables which are probably the largest source for attribute retrieval. Three recall oriented filters are(More)
Traditional search engines return ranked lists of search results. It is up to the user to scroll this list, scan within different documents, and assemble information that fulfill his/her information need. <i>Aggregated search</i> represents a new class of approaches where the information is not only retrieved but also assembled. This is the current(More)
RÉSUMÉ. La recherche d'information agrégée permet, en réponse à une requête, d'agréger des granules d'information provenant de plusieurs sources et de renvoyer à l'utilisateur un ensemble d'informations bien organisées. Le résultat agrégé est une alternative à la traditionnelle liste de documents répondant chacun à une partie du besoin utilisateur. Nous(More)
Major search engines perform what is known as Aggregated Search (AS). They integrate results coming from different vertical search engines (images, videos, news, etc.) with typical Web search results. Aggregated search is relatively new and its advantages need to be evaluated. Some existing works have already tried to evaluate the interest (usefulness) of(More)
Social media monitoring is fast becoming a staple activity for public relations and communications staff, who have a growing mandate to track mentions of organisational entities, projects, or products in social media. However, this task is not trivial because: 1) the mentions may be found across a variety of social media and 2) the keywords used for(More)