Webspace query formulation: an overview Roelof van Zwol Peter M.G. Apers University of Twente,

To find information on the World-Wide Web (WWW), two approaches are generally followed. Browsing the web from a specific starting point, or web-site map, is called search by divergence. The second approach, search by convergence, is followed when using a search engine. Most search engines use a information retrieval strategy, which requires that the user supplies some keywords to find the relevant information. Due to the diversity and unstructuredness of the WWW, both approaches offer only limited query formulation techniques to find the relevant information. When focusing on smaller domains of the Internet, still large collections of documents have to be dealt with, which are presented on a single web-site or Intranet. There the content is more related and structured, which allows us to apply database techniques to the web. The Webspace Method aims at using DB techniques to model and query such document collections. A semantical level of abstraction is obtained, by describing the content of the documents with some high-level concepts, defined in an object-oriented schema. This allows us to bring the power of query formulation as known within a database environment to the web. At the same time, we focus on the integration with Information Retrieval, which allows us to formulate complex content-based queries ove

A Linguistically Motivated Probabilistic Model of Information Retrieval

. This paper presents a new probabilistic model of information retrieval. The most important modeling assumption made is that documents and queries are defined by an ordered sequence of single terms. This assumption is not made in well known existing models of information retrieval, but is essential in the field of statistical natural language processing. Advances already made in statistical natural language processing will be used in this paper to formulate a probabilistic justification for using tf×idf term weighting. The paper shows that the new probabilistic interpretation of tf×idf term weighting might lead to better understanding of statistical ranking mechanisms, for example by explaining how they relate to coordination level ranking. A pilot experiment on the Cranfield test collection indicates that the presented model outperforms the vector space model with classical tf×idf and cosine length normalisation. Keywords: Information Retrieval Theory, Statistical Information Retrie..

Proceedings of the 1998 Winter Simulation Conference

The RESTART method is a widely applicable simulation technique for the estimation of rare event probabilities. The method is based on the idea to restart the simulation in certain system states, in order to generate more occurrences of the rare event. One of the main questions for any RESTART implementation is how and when to restart the simulation, in order to achieve the most accurate results for a fixed simulation effort

ICTs : Reshaping the Voluntary Sector? 1998-1999

Abstract copyright UK Data Service and data collection copyright owner.This research has been shaped by the overarching aims both to begin to map the extent to which voluntary organisations are adopting Information and Communication Technologies (ICTs) and, more particularly, to gain insights into, and to begin to understand and to articulate, the social conditions shaping ICT supported strategic innovations around mission critical and business critical activities within these organisations. It has been shaped, too, by the aim to contribute to theories of institutionalism as these apply explicitly to the voluntary sector within the information society. The specific research objectives are as follows: to map the adoption and application of ICTs within a sample of UK voluntary organisations; to examine the extent to which ICTs are being used to support innovations around key mission critical and business critical activities; to understand the social conditions shaping ICT supported innovations within these organisations, and in doing so to understand the reasons for different patterns of uptake where these occur; to evaluate the significance of ICTs in supporting mission critical and business critical activities within these organisations, including, for example, their contribution to organisational independence and autonomy, deliberative and political participation.Main Topics:The dataset is based upon a largescale questionnaire survey of UK voluntary organisations with incomes ranging from 250,000 pounds per annum to incomes in excess of 11 million pounds. The organisations span a range of fields of activity (e.g. social welfare, conservation, animals) and types of activity (e.g. service provision, campaigning). The dataset permits the uptake and application of information and communication technologies to be examined for association with key variables which include level of organisational income, field of activity, type of activity, and employment of ICTs professionals within the organisations

OF SCIENTIFIC MEASUREMENTS

Illustration of a bend test used in Galileo’s Discorsi e dimostrazioni mathematiche intorno a due nuove scienze attenenti alla meccanica et i movimenti locali (“Two ne

Preface

o

Preface

o