Krzysztof Węcel

Filtering the Web to Feed Data Warehouses

From the Publisher: Information is a key factor in business today, and data warehousing has become a major activity in the development and management of information systems to support the proper flow of information. Unfortunately, the majority of information systems are based on structured information stored in organizational databases, which means that the company is isolated from the business environment by concentrating on their internal data sources only. It is therefore vital that organizations take advantage of external business information, which can be retrieved from Internet services and mechanically organized within the existing information structures. Such a continuously-extending integrated collection of documents and data could facilitate decision-making process in the organization. Filtering the Web to Feed Data Warehouses discusses areas such as: * how to use data warehouse for filtering Web content * how to retrieve relevant information from diverse sources on the Web * how to handle the time aspect * how to mechanically establish links among data warehouse structures and documents filtered from external sources * how to use collected information to increase corporate knowledge and gives a comprehensive example, illustrating the idea of supplying data warehouses with relevant information filtered from the Web.

Modelling the Quality of Attributes in Wikipedia Infoboxes

Quality of data in DBpedia depends on underlying information provided in Wikipedia’s infoboxes. Various language editions can provide different information about given subject with respect to set of attributes and values of these attributes. Our research question is which language editions provide correct values for each attribute so that data fusion can be carried out. Initial experiments proved that quality of attributes is correlated with the overall quality of the Wikipedia article providing them. Wikipedia offers functionality to assign a quality class to an article but unfortunately majority of articles have not been graded by community or grades are not reliable. In this paper we analyse the features and models that can be used to evaluate the quality of articles, providing foundation for the relative quality assessment of infobox’s attributes, with the purpose to improve the quality of DBpedia.

Quality and Importance of Wikipedia Articles in Different Languages

This article aims to analyse the importance of the Wikipedia articles in different languages (English, French, Russian, Polish) and the impact of the importance on the quality of articles. Based on the analysis of literature and our own experience we collected measures related to articles, specifying various aspects of quality that will be used to build the models of articles’ importance. For each language version, the influential parameters are selected that may allow automatic assessment of the validity of the article. Links between articles in different languages offer opportunities in terms of comparison and verification of the quality of information provided by various Wikipedia communities. Therefore, the model can be used not only for a relative assessment of the content of the whole article, but also for a relative assessment of the quality of data contained in their structural parts, the so-called infoboxes.

Hype over Service Oriented Architecture Continues

ZusammenfassungDie intensive Beschäftigung mit SOA führt zu einer weiterhin zunehmenden Zahl von Onlinepublikationen zu dem Thema. Die Flut an Informationen erfordert eine sorgfältige Sichtung. Der Beitrag beginnt mit Definitionen, die in Online-Thesauri zu finden sind oder von verschiedenen Gremien und Softwareherstellern verbreitet werden. Er nennt Blogs, die neueste Informationen zu SOA enthalten. Weitere betriebswirtschaftlich oder technisch orientierte Einführungen, Handbücher und andere Ressourcen zum SOA-Konzept finden sich in verschiedenen Onlinequellen. Die Autoren empfehlen einen Blick auf die Webseiten der EU-finanzierten SOA-Projekte. Dazu gibt es ein Verzeichnis der wichtigsten Organisationen, die sich mit SOA befassen, sowie deren jeweiliges Verständnis des Konzepts.AbstractWidespread promotion of the SOA approach results in an ever growing number of online publications on the subject. Vast amount of resources on SOA requires careful revision. The paper starts with definitions published by online thesauri, various committees and software providers. It lists blogs that publish most up-to-date information about SOA. More about the concept can be found in various online guides, both business- and technically-oriented. The authors also suggest having a look at Web pages of EU-funded projects related to SOA. The article includes a list of the most important organizations working on SOA, along with their views on the concept.

Estimating the Quality of Articles in Russian Wikipedia Using the Logical-Linguistic Model of Fact Extraction

We present the method of estimating the quality of articles in Russian Wikipedia that is based on counting the number of facts in the article. For calculating the number of facts we use our logical-linguistic model of fact extraction. Basic mathematical means of the model are logical-algebraic equations of the finite predicates algebra. The model allows extracting of simple and complex types of facts in Russian sentences. We experimentally compare the effect of the density of these types of facts on the quality of articles in Russian Wikipedia. Better articles tend to have a higher density of facts.

Analysis of References Across Wikipedia Languages

Reliable information sources are important to assess content quality in Wikipedia. Using references readers can verify facts or find more details about described topic. Each Wikipedia article can have over 290 language versions. As articles can be edited independently in any language, even by anonymous users, the information about the same topic may be inconsistent. This also applies to sources that can be found in various language versions of particular article, so the same statement can have different sources. In some cases, Wikipedia users, which speak two or more languages, can transfer information with references between language versions. This paper presents an analysis of using common references in over 10 million articles in several Wikipedia language editions: English, German, French, Russian, Polish, Ukrainian, Belarussian. Also, the study shows the use of similar sources and their number in language sensitive topics.

How much intelligence in the semantic web

The paper discusses the Semantic Web Information Retrieval from the perspective of classical Information Retrieval paradigms and new research carried out with the Semantic Web. It is focused on the impact of new Web incarnation on document indexing, query languages and query resolution, retrieval models and retrieval performance evaluation. Emerging issues are also mentioned: the role of semantic information in classical and SW enabled IR, reasoning and ontology operations necessary for Semantic Web Information Retrieval to function. The challenges of integration of a distributed knowledge base approach with classical document indexing techniques as a general framework for tackling Information Retrieval in new environment are discussed.

Towards an Ontological Representation of Knowledge on the Web

This chapter gives a background on recent developments in Web ontologies, which provide basic means to represent semantic knowledge about the Web. We start with Resource Description Framework to show basic syntax, and further develop many examples in OWL Web Ontology Language to show the expressiveness of this language.

A framework for the quality-based selection and retrieval of open data - a use case from the maritime domain

The paper presents a proposal for a framework for the identification, assessment and selection of open data sources based on certain quality criteria, such as accessibility, relevance, accuracy & reliability, clarity, timeliness & punctuality, and coherence & comparability. The framework concerns mainly open data sources and focuses on their quality. The open data are used to enhance existing internal data and to fuse them with data from other sources. The framework consists of few steps starting from definition of quality criteria based on review of relevant literature and user requirements, then identification of potential sources, sources assessment and selection, and finally data retrieval process. For each step, a specific approach is described, how it may be conducted in practice. The proposed framework is evaluated using a real use case scenario from the maritime domain. The main approach utilized in this use-case is the Delphi method with some characteristics of Analytic Hierarchy Process.

Relative Quality and Popularity Evaluation of Multilingual Wikipedia Articles

Despite the fact that Wikipedia is often criticized for its poor quality, it continues to be one of the most popular knowledge bases in the world. Articles in this free encyclopedia on various topics can be created and edited in about 300 different language versions independently. Our research has showed that in language sensitive topics, the quality of information can be relatively better in the relevant language versions. However, in most cases, it is difficult for the Wikipedia readers to determine the language affiliation of the described subject. Additionally, each language edition of Wikipedia can have own rules in the manual assessing of the content’s quality. There are also differences in grading schemes between language versions: some use a 6–8 grade system to assess articles, and some are limited to 2–3. This makes automatic quality comparison of articles between various languages a challenging task, particularly if we take into account a large number of unassessed articles; some of the Wikipedia language editions have over 99% of articles without a quality grade. The paper presents the results of a relative quality and popularity assessment of over 28 million articles in 44 selected language versions. Comparative analysis of the quality and the popularity of articles in popular topics was also conducted. Additionally, the correlation between quality and popularity of Wikipedia articles of selected topics in various languages was investigated. The proposed method allows us to find articles with information of better quality that can be used to automatically enrich other language editions of Wikipedia.