75,696 research outputs found

    Congenial Web Search : A Conceptual Framework for Personalized, Collaborative, and Social Peer-to-Peer Retrieval

    Get PDF
    Traditional information retrieval methods fail to address the fact that information consumption and production are social activities. Most Web search engines do not consider the social-cultural environment of users' information needs and the collaboration between users. This dissertation addresses a new search paradigm for Web information retrieval denoted as Congenial Web Search. It emphasizes personalization, collaboration, and socialization methods in order to improve effectiveness. The client-server architecture of Web search engines only allows the consumption of information. A peer-to-peer system architecture has been developed in this research to improve information seeking. Each user is involved in an interactive process to produce meta-information. Based on a personalization strategy on each peer, the user is supported to give explicit feedback for relevant documents. His information need is expressed by a query that is stored in a Peer Search Memory. On one hand, query-document associations are incorporated in a personalized ranking method for repeated information needs. The performance is shown in a known-item retrieval setting. On the other hand, explicit feedback of each user is useful to discover collaborative information needs. A new method for a controlled grouping of query terms, links, and users was developed to maintain Virtual Knowledge Communities. The quality of this grouping represents the effectiveness of grouped terms and links. Both strategies, personalization and collaboration, tackle the problem of a missing socialization among searchers. Finally, a concept for integrated information seeking was developed. This incorporates an integrated representation to improve effectiveness of information retrieval and information filtering. An integrated information retrieval process explores a virtual search network of Peer Search Memories in order to accomplish a reputation-based ranking. In addition, the community structure is considered by an integrated information filtering process. Both concepts have been evaluated and shown to have a better performance than traditional techniques. The methods presented in this dissertation offer the potential towards more transparency, and control of Web search

    Online Forum Thread Retrieval using Pseudo Cluster Selection and Voting Techniques

    Full text link
    Online forums facilitate knowledge seeking and sharing on the Web. However, the shared knowledge is not fully utilized due to information overload. Thread retrieval is one method to overcome information overload. In this paper, we propose a model that combines two existing approaches: the Pseudo Cluster Selection and the Voting Techniques. In both, a retrieval system first scores a list of messages and then ranks threads by aggregating their scored messages. They differ on what and how to aggregate. The pseudo cluster selection focuses on input, while voting techniques focus on the aggregation method. Our combined models focus on the input and the aggregation methods. The result shows that some combined models are statistically superior to baseline methods.Comment: The original publication is available at http://www.springerlink.com/. arXiv admin note: substantial text overlap with arXiv:1212.533

    Adversarial Sampling and Training for Semi-Supervised Information Retrieval

    Full text link
    Ad-hoc retrieval models with implicit feedback often have problems, e.g., the imbalanced classes in the data set. Too few clicked documents may hurt generalization ability of the models, whereas too many non-clicked documents may harm effectiveness of the models and efficiency of training. In addition, recent neural network-based models are vulnerable to adversarial examples due to the linear nature in them. To solve the problems at the same time, we propose an adversarial sampling and training framework to learn ad-hoc retrieval models with implicit feedback. Our key idea is (i) to augment clicked examples by adversarial training for better generalization and (ii) to obtain very informational non-clicked examples by adversarial sampling and training. Experiments are performed on benchmark data sets for common ad-hoc retrieval tasks such as Web search, item recommendation, and question answering. Experimental results indicate that the proposed approaches significantly outperform strong baselines especially for high-ranked documents, and they outperform IRGAN in NDCG@5 using only 5% of labeled data for the Web search task.Comment: Published in WWW 201

    The Place of Library and Information Services in Open and Distance Learning in Nigerian Universities

    Get PDF
    This paper emphasises about open and distance learning and the objectives as well as the rationale behind the establishment of open and distance learning. The characteristics of ODL as flexible, portable, transferable, relevant…, and identified the Universities that operate ODL programmes in Nigeria. It also analyses the important role played by library and information services in the open and distance learning in Nigeria. It aids information services in open and distance learning in the dissemination of information to distant learners such as registration of users, orientation/ user education, charging and discharging services, reference services, photocopying services, inter- library loan services, document delivery services, library automation, current awareness services, library guide, selective dissemination of information (SDI) and provision of library website/ links. Challenges such as lack of workout standard rules, lack of consistency of ICTs e – learning centres within the library, no laid down template from the National Universities Commission, lack of information literacy programme among ODL institutions and problem of electricity. The paper proffer remedies for effective services ranging from technical support, technological infrastructural facilities, virtual support programmes, partnership and collaboration and funding, since everything connected to open and distance learning is virtual online delivery and benefit to the distance learners - the library, its resources / information, facilities and services are made virtual for easy dissemination and retrieval of information, so the need for technical support cannot be over emphasised, fully equipped technological infrastructural facilities and resources, virtual supports programmes to enhance the library services to distant learners, partnership and collaborations from other libraries, and above all funding

    Evaluation of a Bayesian inference network for ligand-based virtual screening

    Get PDF
    Background Bayesian inference networks enable the computation of the probability that an event will occur. They have been used previously to rank textual documents in order of decreasing relevance to a user-defined query. Here, we modify the approach to enable a Bayesian inference network to be used for chemical similarity searching, where a database is ranked in order of decreasing probability of bioactivity. Results Bayesian inference networks were implemented using two different types of network and four different types of belief function. Experiments with the MDDR and WOMBAT databases show that a Bayesian inference network can be used to provide effective ligand-based screening, especially when the active molecules being sought have a high degree of structural homogeneity; in such cases, the network substantially out-performs a conventional, Tanimoto-based similarity searching system. However, the effectiveness of the network is much less when structurally heterogeneous sets of actives are being sought. Conclusion A Bayesian inference network provides an interesting alternative to existing tools for ligand-based virtual screening

    Footprints of information foragers: Behaviour semantics of visual exploration

    Get PDF
    Social navigation exploits the knowledge and experience of peer users of information resources. A wide variety of visual–spatial approaches become increasingly popular as a means to optimize information access as well as to foster and sustain a virtual community among geographically distributed users. An information landscape is among the most appealing design options of representing and communicating the essence of distributed information resources to users. A fundamental and challenging issue is how an information landscape can be designed such that it will not only preserve the essence of the underlying information structure, but also accommodate the diversity of individual users. The majority of research in social navigation has been focusing on how to extract useful information from what is in common between users' profiles, their interests and preferences. In this article, we explore the role of modelling sequential behaviour patterns of users in augmenting social navigation in thematic landscapes. In particular, we compare and analyse the trails of individual users in thematic spaces along with their cognitive ability measures. We are interested in whether such trails can provide useful guidance for social navigation if they are embedded in a visual–spatial environment. Furthermore, we are interested in whether such information can help users to learn from each other, for example, from the ones who have been successful in retrieving documents. In this article, we first describe how users' trails in sessions of an experimental study of visual information retrieval can be characterized by Hidden Markov Models. Trails of users with the most successful retrieval performance are used to estimate parameters of such models. Optimal virtual trails generated from the models are visualized and animated as if they were actual trails of individual users in order to highlight behavioural patterns that may foster social navigation. The findings of the research will provide direct input to the design of social navigation systems as well as to enrich theories of social navigation in a wider context. These findings will lead to the further development and consolidation of a tightly coupled paradigm of spatial, semantic and social navigation

    An Analysis of Using Expert Systems and Intelligent Agents for the Virtual Library Project at the Naval Surface Warfare Center-Carderock Division

    Get PDF
    The Virtual Library Project1 at the Naval Surface Warfare Center/Carderock Division (NSWC/CD) is being developed to facilitate the incorporation and use of library documents via the Internet. These documents typically relate to the design and manufacture of ships for the U.S. Navy Fleet. As such, the libraries will store documents that contain not only text but also images, graphs and design configurations. Because of the dynamic nature of digital documents, particularly those related to design, rapid and effective cataloging of these documents becomes challenging. We conducted a research study to analyze the use of expert systems and intelligent agents to support the function of cataloging digital documents. This chapter provides an overview of past research in the use of expert systems and intelligent agents for cataloging digital documents and discusses our recommendations based on NSWC/CD’s requirements

    Digital archiving of manuscripts and other heritage items for conservation and information retrieval

    Get PDF
    Expression of cultural heritage looking from the informatics angle falls into text, images, video and sound categories. ICT can be used to conserve all these heritage items like; the text information consisting of palm leaf manuscripts, stone tablets, handwritten paper documents, old printed records, books, microfilms, fiche etc, images including paintings, drawings, photographs and the like, sound items which includes musical concerts, poetry recitations, chanting of mantras, talks of important persons etc, and video items like archival films historical importance. To retrieve required information from such a large mass of materials in different formats and to transmit them across space and time, there are several limitations. Digital technology allows hitherto unavailable facilities for durable storage and speedy and efficient transmission / retrieval of information contained in all the above formats. Hypertext and hypermedia features of digital media enable integrating text with graphics, sound, video and animation. This paper discusses the international and national efforts for digitizing heritage items, digital archiving solutions available, the possibilities of the media, and the need to follow standards prescribed by organizations like UNESCO to enable easy exchange and pooling of information and documents generated in digital archiving systems at national and international level. The need to develop language technology for local scripts for organizing and preserving our cultural heritage is also stressed
    • …
    corecore