Volker Lüdecke

Otto-Friedrich-Universität Bamberg, Bamberg, Bavaria, Germany

Are you Volker Lüdecke?

Claim your profile

Publications (6)0 Total impact

  • Andreas Henrich, Volker Lüdecke, Daniel Blank
    [Show abstract] [Hide abstract]
    ABSTRACT: Determining the bounds of geographic regions is an important task for geographic search engines which use concept@location-type of queries. The location a user specifies is often not contained in the underlying gazetteer or geographic database, which might be due to vernacular descriptions of regions or because the location is not a geographic region in the narrow sense, which is the case in queries like campground near theme park. In the present paper we describe different ways for automatically determining a geographic footprint for those locations so that a geographic search engine is able to deal with all kinds of location-descriptions. The same approaches can be used to visualize the geographic correlation of arbitrary terms, like the visualization of the spread of certain colloquialisms. The basic idea is to mine locations found in the top documents resulting from a query consisting of the terms the user has chosen to specify the location. We describe how this can be done using kernel density estimation, clustering and a combination thereof.
    16th ACM SIGSPATIAL International Symposium on Advances in Geographic Information Systems, ACM-GIS 2008, November 5-7, 2008, Irvine, California, USA, Proceedings; 01/2008
  • Andreas Henrich, Volker Lüdecke
    [Show abstract] [Hide abstract]
    ABSTRACT: Textual geographic queries to search engines usually consist of the desired concept and also of one or more terms describing a location, which is often the name of a city, which in turn can usually be grounded with the help of a gazetteer. On other occasions, though, the location refers to a (vague) geographic region and may also be a vernacular expression for that region, so that this location specification cannot be found in a gazetteer.
    Weaving Services and People on the World Wide Web, [features some of the cutting-edge research work that were presented at the Workshop Track of the 17th International World Wide Web Conference (WWW 2008) held at Beijing, China, from April 21-25, 2008]; 01/2008
  • Andreas Henrich, Volker Lüdecke
    [Show abstract] [Hide abstract]
    ABSTRACT: In typical concept@location-queries, the location is sometimes given by terms that cannot be found in gazetteers or geographic databases. Such terms usually describe vague geographical regions, but might also include more general terms like mining or theme parks, in which case the corresponding geographic footprint is less obvious. In the present paper we describe our approach to deal with such vague location specifications in geographic queries. Roughly, we determine a geographic representation for these location specifications from toponyms found in the top documents resulting from a query using the terms describing the location. In this paper we describe an efficient process to derive the geographic representation for such situations at query time. Furthermore, we present experiments depicting the performance of our approach as well as the result quality. Our approach allows for an efficient execution of queries such as camping ground near theme park. It can also be used as a standalone-application giving a visual impression of the geographic footprint of arbitrary terms.
    Proceedings of the First International Workshop on Location and the Web, LocWeb 2008, Beijing, China, April 22, 2008; 01/2008
  • Andreas Henrich, Volker Lüdecke
    [Show abstract] [Hide abstract]
    ABSTRACT: A Geographic Information Retrieval (GIR) system for answering geographic queries has to cope with various information needs, which have a wide range of contexts and implicit requirements. A user, for example, who is looking for a place to spend his or her holidays certainly has a different understanding of distance than a user looking for a bar in the city he or she lives in. To get a better understanding of geographic information needs and their implications for GIR systems, we analysed real world (geographic) queries with regard to different facets of geographic references in queries. The results of this analysis are presented in this paper, the aim of which was a classification of the geographic aspects of information needs. We present empirical results and line out possible classification criteria, which could be helpful in designing GIR systems that are able to consider different semantics of geographic references in queries.
    Proceedings of the 4th ACM Workshop On Geographic Information Retrieval, GIR 2007, Lisbon, Portugal, November 9, 2007; 01/2007
  • Datenbank-Spektrum. 01/2006; 18:48-.
  • Raiko Eckstein, Andreas Henrich, Volker Lüdecke
    [Show abstract] [Hide abstract]
    ABSTRACT: Das geographische Information Retrieval (GeoIR) ber¨ ucksichtigt bei Suchanfragen - insb. nach Webseiten - neben dem Inhalt von Dokumenten auch eine r¨ aumliche Komponente, um gezielt nach Seiten suchen zu k¨ onnen, die f¨ ur eine spezifische Region bedeutsam sind. Dazu m¨ ussen GeoIR-Systeme den geographischen Kontext einer Webseite erkennen konnen und in der Lage sein zu entscheiden, ob eine Seite ¨ uberhaupt regional-spezifisch ( " lokal") ist oder einen rein informativen Charakter besitzt, der keinen geographischen Bezug besitzt. Im Folgenden werden Ansatze vorgestellt, Merk- male lokaler Seiten zu ermitteln und diese f¨ ur ei- ne Einteilung von Webseiten in globale und lo- kale Seiten zu verwenden. Dabei sollen insbe- sondere die sprachlichen und geographischen Ei- genschaften deutscher Webseiten ber¨ ucksichtigt werden.
    LWA 2006: Lernen - Wissensentdeckung - Adaptivität, Hildesheim, October 9th-11th 2006, joint workshop event of several interest groups of the German Society for Informatics (GI) - 14th Workshop on Adaptivity and User Modeling in Interactive Systems (ABIS 2006) - Workshop Information Retrieval 2006 of the Special Interest Group Information Retrieval (FGIR 2006) - Workshop on Knowledge and Experience Management (FGWM 2006) - 12th Workshop on Knowledge Discovery, Data Mining, and Machine Learning (KDML 2006); 01/2006