Context-aware OLAP for textual data warehouses

Decision Support Systems (DSS) that leverage business intelligence are based on numerical data and On-line Analytical Processing (OLAP) is often used to implement it. However, business decisions are increasingly dependent on textual data as well. Existing research work on textual data warehouses has the limitation of capturing contextual relationships when comparing only strongly related documents. This paper proposes an Information System (IS) based context-aware model that uses word embedding in conjunction with agglomerative hierarchical clustering algorithms to dynamically categorize documents in order to form the concept hierarchy. The results of the experimental evaluation provide evidence of the effectiveness of integrating textual data into a data warehouse and improving decision making through various OLAP operations

Dynamic topic herarchies and segmented rankings in textual OLAP technology.

Programa de P?s-Gradua??o em Ci?ncia da Computa??o. Departamento de Ci?ncia da Computa??o, Instituto de Ci?ncias Exatas e Biol?gicas, Universidade Federal de Ouro Preto.A tecnologia OLAP tem se consolidado h? 20 anos e recentemente foi redesenhada para que suas dimens?es, hierarquias e medidas possam suportar as particularidades dos dados textuais. A tarefa de organizar dados textuais de forma hier?rquica pode ser resolvida com a constru??o de hierarquias de t?picos. Atualmente, a hierarquia de t?picos ? definida apenas uma vez no cubo de dados, ou seja, para todo o \textit{lattice} de cuboides. No entanto, tal hierarquia ? sens?vel ao conte?do da cole??o de documentos, portanto em um mesmo cubo de dados podem existir c?lulas com conte?dos completamente diferentes, agregando cole??es de documentos distintas, provocando potenciais altera??es na hierarquia de t?picos. Al?m disso, o segmento de texto utilizado na an?lise OLAP tamb?m influencia diretamente nos t?picos elencados por tal hierarquia. Neste trabalho, apresentamos um cubo de dados textual com m?ltiplas e din?micas hierarquias de t?picos. M?ltiplas por serem constru?das a partir de diferentes segmentos de texto e din?micas por serem constru?das para cada c?lula do cubo. Outra contribui??o deste trabalho refere-se ? resposta das consultas multidimensionais. O estado da arte normalmente retorna os top-k documentos mais relevantes para um determinado t?pico. Vamos al?m disso, retornando outros segmentos de texto, como os t?tulos mais significativos, resumos e par?grafos. A abordagem ? projetada em quatro etapas adicionais, onde cada passo atenua um pouco mais o impacto da constru??o de v?rias hierarquias de t?picos e rankings de segmentos por c?lula de cubo. Experimentos que utilizam parte dos documentos da DBLP como uma cole??o de documentos refor?am nossas hip?teses.The OLAP technology emerged 20 years ago and recently has been redesigned so that its dimensions, hierarchies and measures can support the particularities of textual data. Organizing textual data hierarchically can be solved with topic hierarchies. Currently, the topic hierarchy is de ned only once in the data cube, e.g., forthe entire lattice of cubo ids. However, such hierarchy is sensitive to the document collection content. Thus, a data cube cell can contain a collection of documents distinct fromothers in the same cube, causing potential changes in the topic hierarchy. Further more, the text segment used in OLAP analysis also changes this hierarchy. In this work, we present a textual data cube with multiple dynamic topic hierarchies for each cube cell. Multiple hierarchies, since the presented approach builds a topic hierarchy per text segment. Another contribution of this work refers to query response. The state-of-the-art normally returns the top-k documents to the topic selected in the query. We go beyond by returning other text segments, such as the most signi cant titles, abstracts and paragraphs. The approach is designed in four complementary steps and each step attenuates a bit more the impact of building multiple to pic hierarchies and segmented rankings per cube cell. Experiments using part of the DBLP papers as a document collection reinforce our hypotheses

Linking Textual Resources to Support Information Discovery

A vast amount of information is today stored in the form of textual documents, many of which are available online. These documents come from different sources and are of different types. They include newspaper articles, books, corporate reports, encyclopedia entries and research papers. At a semantic level, these documents contain knowledge, which was created by explicitly connecting information and expressing it in the form of a natural language. However, a significant amount of knowledge is not explicitly stated in a single document, yet can be derived or discovered by researching, i.e. accessing, comparing, contrasting and analysing, information from multiple documents. Carrying out this work using traditional search interfaces is tedious due to information overload and the difficulty of formulating queries that would help us to discover information we are not aware of. In order to support this exploratory process, we need to be able to effectively navigate between related pieces of information across documents. While information can be connected using manually curated cross-document links, this approach not only does not scale, but cannot systematically assist us in the discovery of sometimes non-obvious (hidden) relationships. Consequently, there is a need for automatic approaches to link discovery. This work studies how people link content, investigates the properties of different link types, presents new methods for automatic link discovery and designs a system in which link discovery is applied on a collection of millions of documents to improve access to public knowledge

A conceptual framework and a risk management approach for interoperability between geospatial datacubes

De nos jours, nous observons un intérêt grandissant pour les bases de données géospatiales multidimensionnelles. Ces bases de données sont développées pour faciliter la prise de décisions stratégiques des organisations, et plus spécifiquement lorsqu’il s’agit de données de différentes époques et de différents niveaux de granularité. Cependant, les utilisateurs peuvent avoir besoin d’utiliser plusieurs bases de données géospatiales multidimensionnelles. Ces bases de données peuvent être sémantiquement hétérogènes et caractérisées par différent degrés de pertinence par rapport au contexte d’utilisation. Résoudre les problèmes sémantiques liés à l’hétérogénéité et à la différence de pertinence d’une manière transparente aux utilisateurs a été l’objectif principal de l’interopérabilité au cours des quinze dernières années. Dans ce contexte, différentes solutions ont été proposées pour traiter l’interopérabilité. Cependant, ces solutions ont adopté une approche non systématique. De plus, aucune solution pour résoudre des problèmes sémantiques spécifiques liés à l’interopérabilité entre les bases de données géospatiales multidimensionnelles n’a été trouvée. Dans cette thèse, nous supposons qu’il est possible de définir une approche qui traite ces problèmes sémantiques pour assurer l’interopérabilité entre les bases de données géospatiales multidimensionnelles. Ainsi, nous définissons tout d’abord l’interopérabilité entre ces bases de données. Ensuite, nous définissons et classifions les problèmes d’hétérogénéité sémantique qui peuvent se produire au cours d’une telle interopérabilité de différentes bases de données géospatiales multidimensionnelles. Afin de résoudre ces problèmes d’hétérogénéité sémantique, nous proposons un cadre conceptuel qui se base sur la communication humaine. Dans ce cadre, une communication s’établit entre deux agents système représentant les bases de données géospatiales multidimensionnelles impliquées dans un processus d’interopérabilité. Cette communication vise à échanger de l’information sur le contenu de ces bases. Ensuite, dans l’intention d’aider les agents à prendre des décisions appropriées au cours du processus d’interopérabilité, nous évaluons un ensemble d’indicateurs de la qualité externe (fitness-for-use) des schémas et du contexte de production (ex., les métadonnées). Finalement, nous mettons en œuvre l’approche afin de montrer sa faisabilité.Today, we observe wide use of geospatial databases that are implemented in many forms (e.g., transactional centralized systems, distributed databases, multidimensional datacubes). Among those possibilities, the multidimensional datacube is more appropriate to support interactive analysis and to guide the organization’s strategic decisions, especially when different epochs and levels of information granularity are involved. However, one may need to use several geospatial multidimensional datacubes which may be semantically heterogeneous and having different degrees of appropriateness to the context of use. Overcoming the semantic problems related to the semantic heterogeneity and to the difference in the appropriateness to the context of use in a manner that is transparent to users has been the principal aim of interoperability for the last fifteen years. However, in spite of successful initiatives, today's solutions have evolved in a non systematic way. Moreover, no solution has been found to address specific semantic problems related to interoperability between geospatial datacubes. In this thesis, we suppose that it is possible to define an approach that addresses these semantic problems to support interoperability between geospatial datacubes. For that, we first describe interoperability between geospatial datacubes. Then, we define and categorize the semantic heterogeneity problems that may occur during the interoperability process of different geospatial datacubes. In order to resolve semantic heterogeneity between geospatial datacubes, we propose a conceptual framework that is essentially based on human communication. In this framework, software agents representing geospatial datacubes involved in the interoperability process communicate together. Such communication aims at exchanging information about the content of geospatial datacubes. Then, in order to help agents to make appropriate decisions during the interoperability process, we evaluate a set of indicators of the external quality (fitness-for-use) of geospatial datacube schemas and of production context (e.g., metadata). Finally, we implement the proposed approach to show its feasibility

Processing Spatial Keyword Query as a Top-k Aggregation Query

We examine the spatial keyword search problem to retrieve objects of interest that are ranked based on both their spatial proximity to the query location as well as the textual relevance of the object’s keywords. Existing solutions for the problem are based on either using a combination of textual and spatial indexes or using specialized hybrid indexes that integrate the indexing of both textual and spatial attribute values. In this paper, we propose a new approach that is based on modeling the problem as a top-k aggregation problem which enables the design of a scalable and efficient solution that is based on the ubiquitous inverted list index. Our performance study demonstrates that our approach outperforms the state-of-theart hybrid methods by a wide margin

A Survey on Web Usage Mining, Applications and Tools

World Wide Web is a vast collection of unstructured web documents like text, images, audio, video or Multimedia content.  As web is growing rapidly with millions of documents, mining the data from the web is a difficult task. To mine various patterns from the web is known as Web mining. Web mining is further classified as content mining, structure mining and web usage mining. Web usage mining is the data mining technique to mine the knowledge of usage of web data from World Wide Web. Web usage mining extracts useful information from various web logs i.e. users usage history. This is useful for better understanding and serve the people for better web applications. Web usage mining not only useful for the people who access the documents from the World Wide Web, but also it useful for many applications like e-commerce to do personalized marketing, e-services, the government agencies to classify threats and fight against terrorism, fraud detection, to identify criminal activities, the companies can establish better customer relationship and can improve their businesses by analyzing the people buying strategies etc. This paper is going to explain in detail about web usage mining and how it is helpful. Web Usage Mining has seen rapid increase towards research and people communities

SOCNET 2018 - Proceedings of the “Second International Workshop on Modeling, Analysis, and Management of Social Networks and Their Applications”

Modeling, analysis, control, and management of complex social networks represent an important area of interdisciplinary research in an advanced digitalized world. In the last decade social networks have produced significant online applications which are running on top of a modern Internet infrastructure and have been identified as major driver of the fast growing Internet traffic. The "Second International Workshop on Modeling, Analysis and Management of Social Networks and Their Applications" (SOCNET 2018) held at Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany, on February 28, 2018, has covered related research issues of social networks in modern information society. The Proceedings of SOCNET 2018 highlight the topics of a tutorial on "Network Analysis in Python" complementing the workshop program, present an invited talk "From the Age of Emperors to the Age of Empathy", and summarize the contributions of eight reviewed papers. The covered topics ranged from theoretical oriented studies focusing on the structural inference of topic networks, the modeling of group dynamics, and the analysis of emergency response networks to the application areas of social networks such as social media used in organizations or social network applications and their impact on modern information society. The Proceedings of SOCNET 2018 may stimulate the readers' future research on monitoring, modeling, and analysis of social networks and encourage their development efforts regarding social network applications of the next generation.Die Modellierung, Analyse, Steuerung und das Management komplexer sozialer Netzwerke repräsentiert einen bedeutsamen Bereich interdisziplinärer Forschung in einer modernen digitalisierten Welt. Im letzten Jahrzehnt haben soziale Netzwerke wichtige Online Anwendungen hervorgebracht, die auf einer modernen Internet-Infrastruktur ablaufen und als eine Hauptquelle des rasant anwachsenden Internetverkehrs identifiziert wurden. Der zweite internationale Workshop "Modeling, Analysis and Management of Social Networks and Their Applications" (SOCNET 2018) wurde am 28. Februar 2018 an der Friedrich-Alexander-Universität Erlangen-Nürnberg abgehalten und stellte Forschungsergebnisse zu sozialen Netzwerken in einer modernen Informationsgesellschaft vor. Die SOCNET 2018 Proceedings stellen die Themen eines Tutoriums "Network Analysis in Python" heraus, präsentieren einen eingeladenen Beitrag "From the Age of Emperors to the Age of Empathy" und fassen die Ergebnisse von acht begutachteten wissenschaftlichen Beiträgen zusammen. Die abgedeckten Themen reichen von theoretisch ausgerichteten Studien zur Strukturanalyse thematischer Netzwerke, der Modellierung von Gruppendynamik sowie der Netzwerkanalyse von Rettungseinsätzen bis zu den Anwendungsbereichen sozialer Netzwerke, z.B. der Nutzung sozialer Medien in Organisationen sowie der Wirkungsanalyse sozialer Netzwerkanwendungen in modernen Informationsgesellschaften. Die SOCNET 2018 Proceedings sollen die Leser zu neuen Forschungen im Bereich der Messung, Modellierung und Analyse sozialer Netzwerke anregen und sie zur Entwicklung neuer sozialer Netzwerkapplikationen der nächsten Generation auffordern

CRIS-IR 2006

The recognition of entities and their relationships in document collections is an important step towards the discovery of latent knowledge as well as to support knowledge management applications. The challenge lies on how to extract and correlate entities, aiming to answer key knowledge management questions, such as; who works with whom, on which projects, with which customers and on what research areas. The present work proposes a knowledge mining approach supported by information retrieval and text mining tasks in which its core is based on the correlation of textual elements through the LRD (Latent Relation Discovery) method. Our experiments show that LRD outperform better than other correlation methods. Also, we present an application in order to demonstrate the approach over knowledge management scenarios.Fundação para a Ciência e a Tecnologia (FCT) Denmark's Electronic Research Librar