The purpose of this paper is to examine the three main translation methods used in experimental Cross-language information retrieval CLIR research today, namely translation using either machine-readable dictionaries, machine translation systems or corpus-based methods. Working notes from research groups participating in the Text Retrieval Conference TREC and the Cross-Language Evaluation Forum CLEF between 1997 and 2000 have provided the main source material used to discuss the possible advantages and drawbacks that each method presents. It appears that all three approaches have their pros and cons, and because the different researchers tend to favour their own chosen method, it is not possible to establish a "winner approach" to CLIR translation by studying the working notes alone. One should remember however that the present interest in cross-language-applications of information retrieval has arisen as late as in the 1990s, and thus the research is yet in its early stages. The methods discussed in this paper may well be improved, or perhaps replaced by others in the future..

This Master?s thesis examines different retrieval strategies used in Cross-language information retrieval (CLIR). The aim was to investigate if there were any differences between baseline queries and translated queries in retrieval effectiveness; how the retrieval effectiveness was affected by query structuring and if the results differed between different languages. The languages used in this study were Swedish, English and Finnish. 30 topics from the TrecUta collection were translated into Swedish and Finnish.

This thesis deals with one of the main questions within information science: The question about controlled and uncontrolled vocabulary and which of the two that are most effective when it comes to retrieve relevant information from electronic databases. The method used here is literature studies. I have described and examined five empirical studies which has been done in purpose to compare the effectiveness in retrieval with controlled and uncontrolled vocabulary, in the way they are used in retrieval of information in databases. The studies I have examined have also used recall and precision as a value to measure the effectiveness of retrieval. The studies which I have chosen is also limited to deal only with studies that have been done in bibliographic databases.

The aim of this thesis is to describe passage retrieval (PR), with basis in results from various empirical experiments, and to critically investigate different approaches in PR. The main questions to be answered in the thesis are: (1) What characterizes PR? (2) What approaches have been proposed? (3) How well do the approaches work in experimental information retrieval (IR)? PR is a research topic in information retrieval, which instead of retrieving the fulltext of documents, that can lead to information overload for the user, tries to retrieve the most relevant passages in the documents. This technique was investigated studying a number of central articles in the research field. PR can be divided into three different types of approaches based on the segmentation of the documents.

This thesis discusses main problems associated with dictionary-based Cross-language information retrieval as lexical and translational ambiguity of query terms, translation of compounds and phrases, dictionary limitation. The purpose of the study is to investigate how query structure influences the effectiveness of CLIR regarding performance of three query types: original query, unstructured query and structured query. Query structuring refers to the application of #syn-operator to group query terms. The study comprises an experiment that was performed in the InQuery IR system with TrecUta database that contains 550,000 news articles from different American newspapers. 24 topics were used for the experiment.

Syftet med denna uppsats är att undersöka problem samt lösningar i relation till informationsåtervinning över språkliga gränser. Metoden som har använts i uppsatsen är studier av forskningsmaterial inom lingvistik samt främst den relativt nya forskningsdisciplinen Cross-language information retrieval (CLIR). I uppsatsen hävdas att världens alla olikartade språk i dagsläget måste betraktas som ett angeläget problem för informationsvetenskapen, ty språkliga skillnader utgör ännu ett stort hinder för den internationella informationsåtervinning som tekniska framsteg, uppkomsten av Internet, digitala bibliotek, globalisering, samt stora politiska förändringar i ett flertal länder runtom i världen under de senaste åren tekniskt och teoretiskt sett har möjliggjort. I uppsatsens första del redogörs för några universellt erkända lingvistiska skillnader mellan olika språk ? i detta fall främst med exempel från europeiska språk ? och vanliga problem som dessa kan bidra till angående översättningar från ett språk till ett annat.

The purpose of this essay is to examine how high school students (age 13 to 19) search for information on the web and in databases. Furthermore, it aims to look into how critical of sources they are. The questions asked was: how the students search for information in digital media? Which kind of sources do the students use? How they evaluate the information they find? Do they get any education in information retrieval and source evaluation? To answer these questions students were interviewed in groups about their information retrieval behavior. Furthermore two school librarians were interviewed about their experience of the students? information retrieval.During the interviews it was clear that the students had received quite sparse instructions on the subjects of information retrieval and criticism of the sources.

The aim with this thesis came out of a strong interest for Passage Retrieval. Our intention has not been to evaluate an IR-system. Instead our goal has been to analyze the result of indexing documents and their passages. We have been studying the weights of the different terms in the different indices, in comparison with other parameters like frequency, normalized frequency and the inversed document frequency. Further more we have been looking at how the weights are spread using for instance the standard deviation.

This master thesis deals with events, dynamics and problems of mediated information seeking within the context of a new information service called "Book a librarian". The study, based on a survey and interviews both in academic and public libraries and participant observations in academic libraries, has its theoretical base in the cognitive theory of information retrieval interaction. The cognitive view is used to throw light upon the need of an ongoing dialogue during the session in order to detect the information needs of the user and to conduct a successful retrieval of information. The communicative interaction is seen as threepart interaction between the intermediary, the user and the information system, where the current cognitive states of all three participants are involved. The study shows that the cognitive obstacles for a successful mediation and information retrieval are mostly connected to participants current knowledge of the subject and of the retrieval techniques.

The aim of this Masters thesis is, partly, to examine the information needs of lesbians: what discernable information needs they have, how they seek information and which information sources they use. The purpose is also to examine what part fiction plays regarding the information needs mentioned above and how fiction indexing could improve retrieval. The study is conducted through ten qualitative interviews with lesbians as well as through textual analysis. The theoretical framework includes queer theory and theory concerning information needs and uses. The results indicate that lesbians have evident information needs that mostly concern identity.

The purpose of this thesis is to examine the performance of queries that is expanded before translation in comparison with only translation of the queries using a bilingual dictionary, and also to see if the number of terms that was used to expand the queries was of any importance i. e. if many terms from a thesaurus helped or destroyed a query. To answer these questions i used two online thesauri, Rogets thesaurus and Merriam-Webster Online and one printed bilingual dictionary, Norstedts English-Swedish dictionary. Even though the number of examined queries is too small to draw any definite conclusions, the results suggest that expanding using a general thesaurus may have a negative effect on the queries.

The wide spread of the Internet and new information technologies in recent years has come to effect how libraries manage and disseminate information. Search engines like Google are widely used by people who often find the information retrieval systems of libraries to be too complicated. In 2004 Google announced plans to digitise five major library collections. Organisations representing the publishing industry and authors have since then filed lawsuits against Google claiming that Googles scanning of library books infringe the rights holders copyright. Due to Googles potential impact on libraries this thesis aims to examine how Googles digitisation project, Google Book Search, has been received in the library community.

Sweden is getting an aging population and with this comes an increase in neurodegenerative diseases such as Alzheimer?s disease (AD). Bilingualism is also on the rise and this may result in an increase of bilingual people suffering from AD. Due to the linguistic deterioration associated with the illness people with AD, bilingual and monolingual, will be an increasing patient group with speech and language pathologists (SLPs). Word retrieval difficulty is an early symptom of the disease and several strategies to compensate for this have been observed (e.g.

The purpose of this bachelor thesis is to find out how information seeking habits and experiences of people in different generations affects their expectations on information retrieval systems like OPAC. Two OPACs are used, one web-OPAC and one mobile-OPAC. The following questions are asked: how can theories about information seeking behaviors explain why and in which way one seeks information? In which way does information seeking behaviors and habits affect the experience of OPAC? Which differences and/or similarities can be found between the web-OPAC and the mobile-OPAC? How does generational aspects affect experiences and preferences in an information seeking context? The theoretical framework of the thesis is information retrieval with several models about information-seeking/searching needs and behaviors. The empirical data contains interviews with nine people in different generations and protocols about two different OPACs.

The purpose of this study is to examine the difference between three query strategies with respect to retrieval effectiveness. The thesis aims at examining how two types of noun phrases containing a modifier to the head word, which is a noun affect the retrieval performance with regard to recall and precision. The noun phrases in the thesis are of two types: 1) noun phrases containing a modifier to the head word (which is a noun) and which are not dictionary phrases (NF) and 2) dictionary phrases. Both types of noun phrases in this thesis contain at least two words. The queries were executed in Query Performance Analyser, QPA, containing the InQuery system and a sub collection of TREC-Uta documents with its topics.