Literatur zur Informationserschließung

Diese Datenbank enthält über 40.000 Dokumente zu Themen aus den Bereichen Formalerschließung – Inhaltserschließung – Information Retrieval.

© 2015 W. Gödert, TH Köln, Institut für Informationswissenschaft / Powered by litecat, BIS Oldenburg (Stand: 04. Juni 2021)

Suchergebnisse

• 1
  Li, H. ; Wu, H. ; Li, D. ; Lin, S. ; Su, Z. ; Luo, X.: PSI: A probabilistic semantic interpretable framework for fine-grained image ranking.
  In: Journal of the Association for Information Science and Technology. 69(2018) no.12, S.1488-1501.
  
  Abstract: Image Ranking is one of the key problems in information science research area. However, most current methods focus on increasing the performance, leaving the semantic gap problem, which refers to the learned ranking models are hard to be understood, remaining intact. Therefore, in this article, we aim at learning an interpretable ranking model to tackle the semantic gap in fine-grained image ranking. We propose to combine attribute-based representation and online passive-aggressive (PA) learning based ranking models to achieve this goal. Besides, considering the highly localized instances in fine-grained image ranking, we introduce a supervised constrained clustering method to gather class-balanced training instances for local PA-based models, and incorporate the learned local models into a unified probabilistic framework. Extensive experiments on the benchmark demonstrate that the proposed framework outperforms state-of-the-art methods in terms of accuracy and speed.
  
  Inhalt: https://onlinelibrary.wiley.com/doi/10.1002/asi.24068.
  
  Themenfeld: Retrievalalgorithmen
  Behandelte Form: Bilder
  
  
• 2
  Su, Z. ; Li, D. ; Li, H. ; Luo, X.: Boosting attribute recognition with latent topics by matrix factorization.
  In: Journal of the Association for Information Science and Technology. 68(2017) no.7, S.1737-1750.
  
  Abstract: Attribute-based approaches have recently attracted much attention in visual recognition tasks. These approaches describe images by using semantic attributes as the mid-level feature. However, low recognition accuracy becomes the biggest barrier that limits their practical applications. In this paper, we propose a novel framework termed Boosting Attribute Recognition (BAR) for the image recognition task. Our framework stems from matrix factorization, and can explore latent relationships from the aspect of attribute and image simultaneously. Furthermore, to apply our framework in large-scale visual recognition tasks, we present both offline and online learning implementation of the proposed framework. Extensive experiments on 3 data sets demonstrate that our framework achieves a sound accuracy of attribute recognition.
  
  Inhalt: Vgl.: http://onlinelibrary.wiley.com/doi/10.1002/asi.23827/full.
  
  Behandelte Form: Bilder
  
  
• 3
  Wu, S. ; Liu, S. ; Wang, Y. ; Timmons, T. ; Uppili, H. ; Bedrick, S. ; Hersh, W. ; Liu, H,: Intrainstitutional EHR collections for patient-level information retrieval.
  In: Journal of the Association for Information Science and Technology. 68(2017) no.11, S.2636-2648.
  
  Abstract: Research in clinical information retrieval has long been stymied by the lack of open resources. However, both clinical information retrieval research innovation and legitimate privacy concerns can be served by the creation of intrainstitutional, fully protected resources. In this article, we provide some principles and tools for information retrieval resource-building in the unique problem setting of patient-level information retrieval, following the tradition of the Cranfield paradigm. We further include an analysis of parallel information retrieval resources at Oregon Health & Science University and Mayo Clinic that were built on these principles.
  
  Inhalt: Vgl.: http://onlinelibrary.wiley.com/doi/10.1002/asi.23884/full.
  
  Anmerkung: Beitrag in einem Special issue on biomedical information retrieval.
  
  Wissenschaftsfach: Medizin
  
  
• 4
  Jamali, H.R. ; Shahbaztabar, P.: ¬The effects of internet filtering on users' information-seeking behaviour and emotions.
  In: Aslib journal of information management. 69(2017) no.4, S.408-425.
  
  Abstract: Purpose The purpose of this paper is to investigate the relationship between internet filtering, emotions and information-seeking behaviour. Design/methodology/approach In total, 15 postgraduate students at an Iranian university participated in the study which involved a questionnaire, search tasks with think aloud narratives, and interviews. Findings Internet content filtering results in some changes in the information-seeking behaviour of users. Users who face website blocking use a variety of methods to bypass filtering, mostly by using anti-filter software. Filtering encourages users to use channels such as social networking services to share resources and it increases the use of library material by some of the users. Users who face filtering during their search are more likely to visit more pages of results and click on more hits in the results, unlike users who do not experience filtering who rarely go past the first page. Blocking users' access to content stimulates their curiosity and they become more determined to access the content. In terms of the affective aspect, filtering causes several negative emotions (e.g. anger, disgust, sadness and anxiety) and the main reason for these emotions is not the inability to access information but the feeling of being controlled and not having freedom. Research limitations/implications The study was limited to a small number of postgraduate students in social sciences and not generalisable to all user groups. The implication is that in countries where filtering is used, libraries can play an important role in serving users and reducing users negative emotions, especially if libraries can take advantage of technologies such as social media for their services. Originality/value This is first study to address the effects of internet filtering on information-seeking behaviour and emotions. The study shows that internet filtering causes negative emotions and results in some changes in information-seeking behaviour.
  
  Inhalt: Vgl.: https://doi.org/10.1108/AJIM-12-2016-0218.
  
  Themenfeld: Internet
  Land/Ort: Iran
  
  
• 5
  Tenopir, C. ; Levine, K. ; Allard, S. ; Christian, L. ; Volentine, R. ; Boehm, R. ; Nichols, F. ; Nicholas, D. ; Jamali, H.R. ; Herman, E. ; Watkinson, A.: Trustworthiness and authority of scholarly information in a digital age : results of an international questionnaire.
  In: Journal of the Association for Information Science and Technology. 67(2016) no.10, S.2344-2361.
  
  Abstract: An international survey of over 3,600 researchers examined how trustworthiness and quality are determined for making decisions on scholarly reading, citing, and publishing and how scholars perceive changes in trust with new forms of scholarly communication. Although differences in determining trustworthiness and authority of scholarly resources exist among age groups and fields of study, traditional methods and criteria remain important across the board. Peer review is considered the most important factor for determining the quality and trustworthiness of research. Researchers continue to read abstracts, check content for sound arguments and credible data, and rely on journal rankings when deciding whether to trust scholarly resources in reading, citing, or publishing. Social media outlets and open access publications are still often not trusted, although many researchers believe that open access has positive implications for research, especially if the open access journals are peer reviewed.
  
  Inhalt: Vgl.: http://onlinelibrary.wiley.com/doi/10.1002/asi.23598/full.
  
  Themenfeld: Benutzerstudien
  Wissenschaftsfach: Kommunikationswissenschaften
  
  
• 6
  Ntuli, H. ; Inglesi-Lotz, R. ; Chang, T. ; Pouris, A.: Does research output cause economic growth or vice versa? : evidence from 34 OECD countries.
  In: Journal of the Association for Information Science and Technology. 66(2015) no.8, S.1709-1716.
  
  Abstract: The causal relation between research and economic growth is of particular importance for political support of science and technology as well as for academic purposes. This article revisits the causal relationship between research articles published and economic growth in Organisation for Economic Co-operation and Development (OECD) countries for the period 1981-2011, using bootstrap panel causality analysis, which accounts for cross-section dependency and heterogeneity across countries. The article, by the use of the specific method and the choice of the country group, makes a contribution to the existing literature. Our empirical results support unidirectional causality running from research output (in terms of total number of articles published) to economic growth for the US, Finland, Hungary, and Mexico; the opposite causality from economic growth to research articles published for Canada, France, Italy, New Zealand, the UK, Austria, Israel, and Poland; and no causality for the rest of the countries. Our findings provide important policy implications for research policies and strategies for OECD countries.
  
  Inhalt: Vgl.: http://onlinelibrary.wiley.com/doi/10.1002/asi.23285/abstract.
  
  Themenfeld: Informetrie
  
  
• 7
  Nicholas, D. ; Clark, D. ; Rowlands, I. ; Jamali, H.R.: Information on the go : a case study of Europeana mobile users.
  In: Journal of the American Society for Information Science and Technology. 64(2013) no.7, S.1311-1322.
  
  Abstract: According to estimates the mobile device will soon be the main platform for searching the web, and yet our knowledge of how mobile consumers use information, and how that differs from desktops/laptops users, is imperfect. The paper sets out to correct this through an analysis of the logs of a major cultural website, Europeana. The behavior of nearly 70,000 mobile users was examined over a period of more than a year and compared with that for PC users of the same site and for the same period. The analyses conducted include: size and growth of use, time patterns of use; geographical location of users, digital collections used; comparative information-seeking behavior using dashboard metrics, clustering of users according to their information seeking, and user satisfaction. The main findings were that mobile users were the fastest-growing group and will rise rapidly to a million by December 2012 and that their visits were very different in the aggregate from those arising from fixed platforms. Mobile visits could be described as being information "lite": typically shorter, less interactive, and less content viewed per visit. Use took a social rather than office pattern, with mobile use peaking at nights and weekends. The variation between different mobile devices was large, with information seeking on the iPad similar to that for PCs and laptops and that for smartphones very different indeed. The research further confirms that information-seeking behavior is platform-specific and the latest platforms are changing it all again. Websites will have to adapt.
  
  Themenfeld: Information Gateway ; Benutzerstudien
  Objekt: Europeana
  
  
• 8
  Li, H. ; Bhowmick, S.S. ; Sun, A.: AffRank: affinity-driven ranking of products in online social rating networks.
  In: Journal of the American Society for Information Science and Technology. 62(2011) no.7, S.1345-1359.
  
  Abstract: Large online social rating networks (e.g., Epinions, Blippr) have recently come into being containing information related to various types of products. Typically, each product in these networks is associated with a group of members who have provided ratings and comments on it. These people form a product community. A potential member can join a product community by giving a new rating to the product. We refer to this phenomenon of a product community's ability to "attract" new members as product affinity. The knowledge of a ranked list of products based on product affinity is of much importance for implementing policies, marketing research, online advertisement, and other applications. In this article, we identify and analyze an array of features that exert effect on product affinity and propose a novel model, called AffRank, that utilizes these features to predict the future rank of products according to their affinities. Evaluated on two real-world datasets, we demonstrate the effectiveness and superior prediction quality of AffRank compared with baseline methods. Our experiments show that features such as affinity rank history, affinity evolution distance, and average rating are the most important factors affecting future rank of products. At the same time, interestingly, traditional community features (e.g., community size, member connectivity, and social context) have negligible influence on product affinities.
  
  
  
• 9
  Jamali, H.R. ; Nicholas, D.: Interdisciplinarity and the information-seeking behavior of scientists.
  In: Information processing and management. 46(2010) no.2, S.233-243.
  
  Abstract: Adopting an intradisciplinary perspective, this article evaluates the information-seeking behavior of academics from different subfields of physics and astronomy. It investigates the effect of interdisciplinarity (reliance on the literature of other subjects) and the scatter of literature on two aspects of the information-seeking behavior: methods used for keeping up-to-date and for identifying articles. To this end a survey of 114 PhD students and staff at the Department of Physics and Astronomy at the University College London was carried out. The findings showed that the subfields that are more interdisciplinary or have a more scattered literature are more likely to use general search facilities for finding information. The study also showed that cross-disciplinary use of the literature is not necessarily an indicator of scattered literature. The study reveals intradisciplinary differences among physicists and astronomers in terms of their information-seeking behavior and highlights the risk of overlooking the characteristics of information-seeking behavior of specialized subject communities by focusing on very broad subject categories.
  
  Themenfeld: Informationsdienstleistungen
  Wissenschaftsfach: Physik ; Astronomie
  
  
• 10
  Nicholas, D. ; Huntington, P. ; Jamali, H.R. ; Rowlands, I. ; Fieldhouse, M.: Student digital information-seeking behaviour in context.
  In: Journal of documentation. 65(2009) no.1, S.106-132.
  
  Abstract: Purpose - This study provides evidence on the actual information-seeking behaviour of students in a digital scholarly environment, not what they thought they did. It also compares student information-seeking behaviour with that of other academic communities, and, in some cases, for practitioners. Design/methodology/approach - Data were gathered as part of CIBER's ongoing Virtual Scholar programme. In particular log data from two digital journals libraries, Blackwell Synergy and OhioLINK, and one e-book collection (Oxford Scholarship Online) are utilized. Findings - The study showed a distinctive form of information-seeking behaviour associated with students and differences between them and other members of the academic community. For example, students constituted the biggest users in terms of sessions and pages viewed, and they were more likely to undertake longer online sessions. Undergraduates and postgraduates were the most likely users of library links to access scholarly databases, suggesting an important "hot link" role for libraries. Originality/value - Few studies have focused on the actual (rather than perceived) information-seeking behaviour of students. The study fills that gap.
  
  Themenfeld: Informationsdienstleistungen
  
  
• 11
  Lee, K.C. ; Lee, N. ; Li, H.: ¬A particle swarm optimization-driven cognitive map approach to analyzing information systems project risk.
  In: Journal of the American Society for Information Science and Technology. 60(2009) no.6, S.1208-1221.
  
  Abstract: Project risks encompass both internal and external factors that are interrelated, influencing others in a causal way. It is very important to identify those factors and their causal relationships to reduce the project risk. In the past, most IT companies evaluate project risk by roughly measuring the related factors, but ignoring the important fact that there are complicated causal relationships among them. There is a strong need to develop more effective mechanisms to systematically judge all factors related to project risk and identify the causal relationships among those factors. To accomplish this research objective, our study adopts a cognitive map (CM)-based mechanism called the MACOM (Multi-Agents COgnitive Map), where CM is represented by a set of multi-agents, each embedded with basic intelligence to determine its causal relationships with other agents. CM has proven especially useful in solving unstructured problems with many variables and causal relationships; however, simply applying CM to project risk management is not enough because most causal relationships are hard to identify and measure exactly. To overcome this problem, we have borrowed a multi-agent metaphor in which CM is represented by a set of multi-agents, and project risk is explained through the interaction of the multi-agents. Such an approach presents a new computational capability for resolving complicated decision problems. Using the MACOM framework, we have proved that the task of resolving the IS project risk management could be systematically and intelligently solved, and in this way, IS project managers can be given robust decision support.
  
  
  
• 12
  Li, M. ; Li, H. ; Zhou, Z.-H.: Semi-supervised document retrieval.
  In: Information processing and management. 45(2009) no.3, S.341-355.
  
  Abstract: This paper proposes a new machine learning method for constructing ranking models in document retrieval. The method, which is referred to as SSRank, aims to use the advantages of both the traditional Information Retrieval (IR) methods and the supervised learning methods for IR proposed recently. The advantages include the use of limited amount of labeled data and rich model representation. To do so, the method adopts a semi-supervised learning framework in ranking model construction. Specifically, given a small number of labeled documents with respect to some queries, the method effectively labels the unlabeled documents for the queries. It then uses all the labeled data to train a machine learning model (in our case, Neural Network). In the data labeling, the method also makes use of a traditional IR model (in our case, BM25). A stopping criterion based on machine learning theory is given for the data labeling process. Experimental results on three benchmark datasets and one web search dataset indicate that SSRank consistently and almost always significantly outperforms the baseline methods (unsupervised and supervised learning methods), given the same amount of labeled data. This is because SSRank can effectively leverage the use of unlabeled data in learning.
  
  Themenfeld: Retrievalalgorithmen
  
  
• 13
  Kuo, J.-S. ; Li, H. ; Yang, Y.-K.: Active learning for constructing transliteration lexicons from the Web.
  In: Journal of the American Society for Information Science and Technology. 59(2008) no.1, S.126-135.
  
  Abstract: This article presents an adaptive learning framework for Phonetic Similarity Modeling (PSM) that supports the automatic construction of transliteration lexicons. The learning algorithm starts with minimum prior knowledge about machine transliteration and acquires knowledge iteratively from the Web. We study the unsupervised learning and the active learning strategies that minimize human supervision in terms of data labeling. The learning process refines the PSM and constructs a transliteration lexicon at the same time. We evaluate the proposed PSM and its learning algorithm through a series of systematic experiments, which show that the proposed framework is reliably effective on two independent databases.
  
  Themenfeld: Computerlinguistik
  
  
• 14
  Nicholas, D. ; Huntington, P. ; Jamali, H.R. ; Rowlands, I. ; Dobrowolski, T. ; Tenopir, C.: Viewing and reading behaviour in a virtual environment : the full-text download and what can be read into it.
  In: Aslib proceedings. 60(2008) no.3, S.185-198.
  
  Abstract: Purpose - This article aims to focus on usage data in respect to full-text downloads of journal articles, which is considered an important usage (satisfaction) metric by librarians and publishers. The purpose is to evaluate the evidence regarding full-text viewing by pooling together data on the full-text viewing of tens of thousands of users studied as part of a number of investigations of e-journal databases conducted during the Virtual Scholar research programme. Design/methodology/approach - The paper reviews the web logs of a number of electronic journal libraries including OhioLINK and ScienceDirect using Deep Log Analysis, which is a more sophisticated form of transactional log analysis. The frequency, characteristics and diversity of full-text viewing are examined. The article also features an investigation into the time spent online viewing full-text articles in order to get a clearer understanding of the significance of full-text viewing, especially in regard to reading. Findings - The main findings are that there is a great deal of variety amongst scholars in their full-text viewing habits and that a large proportion of views are very cursory in nature, although there is survey evidence to suggest that reading goes on offline. Originality/value - This is the first time that full-text viewing evidence is studied on such a large scale.
  
  Themenfeld: Elektronisches Publizieren
  
  
• 15
  Rowlands, I. ; Nicholas, D. ; Williams, P. ; Huntington, P. ; Fieldhouse, M. ; Gunter, B. ; Withey, R. ; Jamali, H.R. ; Dobrowolski, T. ; Tenopir, C.: ¬The Google generation : the information behaviour of the researcher of the future.
  In: Aslib proceedings. 60(2008) no.4, S.290-310.
  
  Abstract: Purpose - This article is an edited version of a report commissioned by the British Library and JISC to identify how the specialist researchers of the future (those born after 1993) are likely to access and interact with digital resources in five to ten years' time. The purpose is to investigate the impact of digital transition on the information behaviour of the Google Generation and to guide library and information services to anticipate and react to any new or emerging behaviours in the most effective way. Design/methodology/approach - The study was virtually longitudinal and is based on a number of extensive reviews of related literature, survey data mining and a deep log analysis of a British Library and a JISC web site intended for younger people. Findings - The study shows that much of the impact of ICTs on the young has been overestimated. The study claims that although young people demonstrate an apparent ease and familiarity with computers, they rely heavily on search engines, view rather than read and do not possess the critical and analytical skills to assess the information that they find on the web. Originality/value - The paper reports on a study that overturns the common assumption that the "Google generation" is the most web-literate.
  
  Anmerkung: Vgl. auch: Rowlands, I.: Google generation: issues in information literacy. In: http://www.lucis.me.uk/retrieval%20issues.pdf.
  
  Themenfeld: Informationsdienstleistungen ; Suchmaschinen ; Internet
  Wissenschaftsfach: Kommunikationswissenschaften
  Land/Ort: GB
  
  
• 16
  Huntington, P. ; Nicholas, D. ; Jamali, H.R.: Website usage metrics : a re-assessment of session data.
  In: Information processing and management. 44(2008) no.1, S.358-372.
  
  Abstract: Metrics derived from user visits or sessions provide a means of evaluating Websites and an important insight into online information seeking behaviour, the most important of them being the duration of sessions and the number of pages viewed in a session, a possible busyness indicator. However, the identification of session (termed often 'sessionization') is fraught with difficulty in that there is no way of determining from a transactional log file that a user has ended their session. No one logs out. Instead a session delimiter has to be applied and this is typically done on the basis of a standard period of inactivity. To date researchers have discussed the issue of a time out delimiter in terms of a single value and if a page view time exceeds the cut-off value the session is deemed to have ended. This approach assumes that page view time is a single distribution and that the cut-off value is one point on that distribution. The authors however argue that page time distribution is composed of a number of quite separate view time distributions because of the marked differences in view times between pages (abstract, contents page, full text). This implies that a number of timeout delimiters should be applied. Employing data from a study of the OhioLINK digital journal library, the authors demonstrate how the setting of a time out delimiter impacts on the estimate of page view time and the number of estimated session. Furthermore, they also show how a number of timeout delimiters might apply and they argue that this gives a better and more robust estimate of the number of sessions, session time and page view time compared to an application of a single timeout delimiter.
  
  Themenfeld: Internet
  
  
• 17
  Qin, T. ; Zhang, X.-D. ; Tsai, M.-F. ; Wang, D.-S. ; Liu, T.-Y. ; Li, H.: Query-level loss functions for information retrieval.
  In: Information processing and management. 44(2008) no.2, S.838-855.
  
  Abstract: Many machine learning technologies such as support vector machines, boosting, and neural networks have been applied to the ranking problem in information retrieval. However, since originally the methods were not developed for this task, their loss functions do not directly link to the criteria used in the evaluation of ranking. Specifically, the loss functions are defined on the level of documents or document pairs, in contrast to the fact that the evaluation criteria are defined on the level of queries. Therefore, minimizing the loss functions does not necessarily imply enhancing ranking performances. To solve this problem, we propose using query-level loss functions in learning of ranking functions. We discuss the basic properties that a query-level loss function should have and propose a query-level loss function based on the cosine similarity between a ranking list and the corresponding ground truth. We further design a coordinate descent algorithm, referred to as RankCosine, which utilizes the proposed loss function to create a generalized additive ranking model. We also discuss whether the loss functions of existing ranking algorithms can be extended to query-level. Experimental results on the datasets of TREC web track, OHSUMED, and a commercial web search engine show that with the use of the proposed query-level loss function we can significantly improve ranking accuracies. Furthermore, we found that it is difficult to extend the document-level loss functions to query-level loss functions.
  
  
  
• 18
  Jamali, H.R. ; Nicholas, D.: Information-seeking behaviour of physicists and astronomers.
  In: Aslib proceedings. 60(2008) no.5, S.444-462.
  
  Abstract: Purpose - The study aims to examines two aspects of information seeking behaviour of physicists and astronomers including methods applied for keeping up-to-date and methods used for finding articles. The relationship between academic status and research field of users with their information seeking behaviour was investigated. Design/methodology/approach - Data were gathered using a questionnaire survey of PhD students and staff of the Department of Physics and Astronomy at University College London; 114 people (47.1 per cent response rate) participated in the survey. Findings - The study reveals differences among subfields of physics and astronomy in terms of information-seeking behaviour, highlights the need for and the value of looking at narrower subject communities within disciplines for a deeper understanding of the information behaviour of scientists. Originality/value - The study is the first to deeply investigate intradisciplinary dissimilarities of information-seeking behaviour of scientists in a discipline. It is also an up-to-date account of information seeking behaviour of physicists and astronomers.
  
  Themenfeld: Informationsdienstleistungen ; Benutzerstudien
  Wissenschaftsfach: Astronomie ; Physik
  
  
• 19
  Rowlands, I. ; Nicholas, D. ; Jamali, H.R. ; Huntington, P.: What do faculty and students really think about e-books?.
  In: Aslib proceedings. 59(2007) no.6, S.489-511.
  
  Abstract: Purpose - The purpose of this article is to report on a large-scale survey that was carried out to assess academic users' awareness, perceptions and existing levels of use of e-books. The survey also seeks to find out about the purposes to which electronic books were put, and to obtain an understanding of the most effective library marketing and communication channels. Design/methodology/approach - An e-mail invitation to participate in the survey was distributed to all UCL staff and students (approximately 27,000) in November 2006, and 1,818 completions were received, an effective response rate of at least 6.7 per cent. Statistical analyses were carried out on the data using Software Package for Social Sciences (SPSS). Findings - The survey findings point to various ways in which user uptake and acceptance of e-books may be encouraged. Book discovery behaviour, a key issue for publishers and librarians in both print and electronic environments, emerges as a critical focus for service delivery and enhancement. Originality/value - The survey is part of an action research project, CIBER's SuperBook, that will further investigate the issues raised in this initial benchmarking survey using deep log analysis and qualitative methods. The paper partly fills the gap in the literature on e-books which has mainly focused on usage and not the users.
  
  Themenfeld: Elektronisches Publizieren
  Land/Ort: GB
  
  
• 20
  Nicholas, D. ; Huntington, P. ; Jamali, H.R. ; Dobrowolski, T.: Characterising and evaluating information seeking behaviour in a digital environment : Spotlight on the 'bouncer'.
  In: Information processing and management. 43(2007) no.4, S.1085-1102.
  
  Abstract: The paper delineates and explains an emerging, but significant, form of digital information seeking behaviour among information consumers, which the authors have called 'bouncing'. The evidence for this behaviour has emerged from five years of deep log analysis studies - an advanced form of transaction log analysis - of a wide range of users of digital information resources. Much of the evidence and discussion provided comes from the scholarly communication field. Two main bouncing metrics were applied in the log studies: site penetration, which is the number of items or pages viewed in a session, and return visits. The evidence shows that (1) a high proportion of people view just a few items or pages during a visit to a site and, (2) a high proportion of visitors either do not come back to the site or they did so infrequently. Typically those who penetrated a site least tended to return the least frequently. These people are termed 'bouncers'. They bounce into the site and then bounce out again, presumably, to another site, as a high proportion of them do not appear to come back again. Possible explanations - negative and positive, for the form of behaviour are discussed.