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Document clustering offers the potential of supporting users in interactive retrieval, especially when users have problems in specifying their information need precisely. In this paper, we present a theoretic foundation for optimum document clustering. Key idea is to base cluster analysis and evalutation on a set of queries, by defining documents as being similar if they are relevant to the same queries. Three components are essential within our optimum clustering framework, OCF: (1) a set of queries, (2) a probabilistic retrieval method, and (3) a document similarity metric. After introducing an appropriate validity measure, we define optimum clustering with respect to the estimates of the relevance probability for the query-document pairs under consideration. Moreover, we show that well-known clustering methods are implicitly based on the three components, but that they use heuristic design decisions for some of them. We argue that with our framework more targeted research for developing better document clustering methods becomes possible. Experimental results demonstrate the potential of our considerations. [ABSTRACT FROM AUTHOR]

Objective: Endometriosis is considered an estrogen-dependent disease of women in their reproductive age and characterized by the occurrence of stromal cells and endometrial-like glands outside the uterine cavity. Patient: A report of a 9-year-old premenarcheal girl who was transferred to the Endometriosis Research Center Berlin-Brandenburg Level III (Academic Teaching Hospital) because of cyclic pelvic pain since her 8th year of life. Interventions: History, examination, abdominal ultrasound, laboratory tests, laparoscopic resection of visible lesions. Paraffin-embedded histology (HE staining) and immunohistochemistry. Results: Endometriosis, defined as the presence of stromal tissue and epithelial glands, was confirmed both by HE staining and immunohistochemistry (CD10), respectively. Conclusions: Young pre- or perimenarcheal girls with chronic/cyclic pelvic pain can have endometriosis, and thus the possibility of endometriosis should be included in the differential diagnosis. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract The classical Probability Ranking Principle (PRP) forms the theoretical basis,for probabilistic Information Retrieval (IR) models, which are dominating IR theory since,about 20 years. However, the assumptions underlying the PRP often do not hold, and its,view is too narrow for interactive information retrieval (IIR). In this article, a new theoretical, framework for interactive retrieval is proposed: The basic idea is that during IIR, a,user moves between situations. In each situation, the system presents to the user a list of,choices, about which s/he has to decide, and the first positive decision moves the user to a,new situation. Each choice is associated with a number of cost and probability parameters.,Based on these parameters, an optimum ordering of the choices can the derived-the PRP,for IIR. The relationship of this rule to the classical PRP is described, and issues of further,research are pointed out. [ABSTRACT FROM AUTHOR]

Digital libraries (DLs) are new and innovative information systems, under constant development and change, and therefore evaluation is of critical importance to ensure not only their correct evolution but also their acceptance by the user and application communities. The Evaluation activity of the DELOS Network of Excellence has performed a large-scale survey of current DL evaluation activities. This study has resulted in a description of the state of the art in the field, which is presented in this paper. The paper also proposes a new framework for the evaluation of DLs, as well as for recording, describing and analyzing the related research field. The framework includes a methodology for the classification of current evaluation procedures. The objective is to provide a set of flexible and adaptable guidelines for DL evaluation. [ABSTRACT FROM AUTHOR]

Content-oriented XML retrieval approaches aim at a more focused retrieval strategy: Instead of retrieving whole documents, document components that are exhaustive to the information need while at the same time being as specific as possible should be retrieved. In this article, we show that the evaluation methods developed for standard retrieval must be modified in order to deal with the structure of XML documents. More precisely, the size and overlap of document components must be taken into account. For this purpose, we propose a new effectiveness metric based on the definition of a concept space defined upon the notions of exhaustiveness and specificity of a search result. We compare the results of this new metric by the results obtained with the official metric used in INEX, the evaluation initiative for content-oriented XML retrieval. [ABSTRACT FROM AUTHOR]

This paper proposes two probabilistic extensions of variants of the OWL Lite description language, which are essential for advanced applications like information retrieval. The first step follows the axiomatic approach of combining description logics and Horn clauses: Subsets of OWL Lite are mapped in a sound and complete way onto Horn predicate logics (Datalog variants). Compared to earlier approaches, a larger fraction of OWL Lite can be transformed by switching to Datalog with equality in the head; however, some OWL Lite constructs cannot be transformed completely into Datalog. By using probabilistic Datalog, the new probabilistic OWL Lite subsets (both with support for Horn rules) are defined, and the semantics are given by the semantics of the corresponding probabilistic Datalog program. As inference engines for probabilistic Datalog are available, description logics and information retrieval systems can easily be combined. [ABSTRACT FROM AUTHOR]

Content-only queries in hierarchically structured documents should retrieve the most specific document nodes which are exhaustive to the information need. For this problem, we investigate two methods of augmentation, which both yield high retrieval quality. As retrieval effectiveness, we consider the ratio of retrieval quality and response time; thus, fast approximations to the ‘correct’ retrieval result may yield higher effectiveness. We present a classification scheme for algorithms addressing this issue, and adopt known algorithms from standard document retrieval for XML retrieval. As a new strategy, we propose incremental-interruptible retrieval, which allows for instant presentation of the top ranking documents. We develop a new algorithm implementing this strategy and evaluate the different methods with the INEX collection. [ABSTRACT FROM AUTHOR]

This special issue contains articles describing XML retrieval approaches developed and evaluated during the second year of INEX, the evaluation initiative for XML retrieval. [ABSTRACT FROM AUTHOR]

Presents probabilistic version of Datalog (function-free Horn clause predicate logic) and its use for information retrieval. Advantages of probabilistic Datalog (pD) to information retrieval; Difference between pD and Datalog; Comparison between pD approach and other interpretations of probabilistic rules.

Presents information on a study which developed a general decision-theoretic model to database selection in networked information retrieval (NIR). Optimum database selection; Discussion; Conclusion.

Presents a probabilistic relational algebra (PRA) which is a generalization of standard relational algebra. Assignment of probabilistic weights to tuples; Conformation of the result to the probabilistic model; Discussion of complexity issues; Indication of possibilities for optimization.

An introduction is presented in which the editor discusses various articles within the issue on topics including applicability of benchmark in interpretation of bibliographic records; retrieval of videos content based on concepts; and a case study with Dublin Core Terms using the Dendro platform.

The article discusses various reports published within the issue, including one by Miro Lehtonen on the preparation of heterogeneous XML and another by Carolyn Crouch on dynamic element retrieval in a structured environment.

A letter to the editor is presented in response to an article about trial and suggestions that the use of antibiotics may cause a greater benefit in neonatal morbidity prior to 27-30 weeks of gestation.

Text clustering is an established technique for improving quality in information retrieval, for both centralized and distributed environments. However, traditional text clustering algorithms fail to scale on highly distributed environments, such as peer-to-peer networks. Our algorithm for peer-to-peer clustering achieves high scalability by using a probabilistic approach for assigning documents to clusters. It enables a peer to compare each of its documents only with very few selected clusters, without significant loss of clustering quality. The algorithm offers probabilistic guarantees for the correctness of each document assignment to a cluster. Extensive experimental evaluation with up to 1 million peers and 1 million documents demonstrates the scalability and effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

As a important part of endocrine surgery, laparoscopic surgery has become the gold standard for the treatment of benign symptomatic ovarian cysts refractory to medical treatment. In fact, the stripping technique seems to be the most common technique used for ovarian cyst surgery. After stripping the cystic wall, the subsequent bleeding of the ovarian stromal wound ground is usually controlled by bipolar coagulation or/and by suturing. Potentially, the surgery-induced ovarian tissue damage will be increased by heat and/or by sutures. In respect to intraovarian hemostasis, the use of gelantine-thrombin-matrix might protect from additional ovarian tissue damage, which is of great importance for the ovarian reproductive function in woman. For the first time, our data do support a promising laparoscopic technique demonstrating ovarian cystectomy without any bipolar coagulation and/or suturing of ovarian tissue using a gelantine-thrombin-matrix sealant (FloSeal) as a new tool to control post-cystectomy ovarian wound bleeding. [ABSTRACT FROM AUTHOR]

In this article, we describe our interdisciplinary project ‘Rule-based search in text databases with nonstandard orthography (RSNSR)’ in support of the conservation of cultural heritage, especially for the German reception of the philosopher Nietzsche. We present a rule-based fuzzy search engine that allows users to retrieve text data independently of its orthographical realization. The rules used are derived from statistical analyses, historical publications, linguistic principles, and expert knowledge. Our Web-based tool is intended for experts as well as interested amateurs. Along with its present features, further functions are currently worked out. Among them are automatic rule derivation and finer result classification through a generalized Levenshtein similarity measure. Our work is associated with the recently launched project Deutsch Diachron Digital (DDD) to build a complete diachronic corpus of German for the first time with texts from the ninth century (Old High German) to the present (Modern German). [ABSTRACT FROM AUTHOR]