An experimental comparison of the effectiveness of computers and humans as search intermediaries

The Effects of Hypertext on Reader Knowledge Representation

The goal of this research was to evaluate the effects of hypertext as an intra-document text format. Subjects read two articles on a color VDT, one in linear and one in hypertext format. Half of the subjects read general interest articles with instructions for casual reading and the other half read technical articles with instructions to learn the material. Afterward, subjects were given free recall tests, question probe tests, and a preference questionnaire. Results indicated that for both types of article, the linear format resulted in greater memory for the basic ideas contained in the articles. Also, for the general interest articles, subjects reading in linear format assimilated more of the macro-structure than subjects reading in the hypertext format. Consistent with these findings, a majority of the subjects expressed a preference for the linear format and perceived it as requiring less mental effort than reading hypertext. These results suggest that, at least under some circumstances, hypertext can interfere with normal cognitive processes.

A study of users’ performance and satisfaction with the Web of Science IR interface

This paper reports on an empirical study of users’ performance and satisfaction with the Web of Science interface. Two different search groups (novice and experienced) participated in the study. They carried out seven search tasks and their performance was recorded through transaction logging and computer screen recording. Data were captured on the time taken, search terms used, success score and error rates. After completion of search tasks, they completed a questionnaire on their satisfaction with the interface. The performance data showed that overall experienced users performed better than the novice group. Differences were significant in success score and error rates between the groups. Performance differences also existed on factors such as gender and previous online search training. Experienced female searchers performed best in terms of success score and error rates whereas the novice male group performed worst. Untrained users were more successful and made fewer errors than the trained group. Participants held neither highly positive nor highly negative perceptions about the Web of Science interface. Novice searchers were significantly more satisfied with the interface than the experienced group. Participants also noted both positive and negative features in the interface. This information could be used to redesign the present Web of Science interface.

Online: views on costs and cost-effectiveness

Interviews with online users—both intermediaries and end—users—in The Media and The City are used as the basis for an assessment of funding and cost issues. Few experienced any difficulties obtaining financial support for online activities, with most justifying the expenditure on the grounds of savings in staff, material and space. The 'information-is-free' syn drome continues to restrict the online industry, and the atti tudes of some database hosts to this barrier are reported. The issue of cost-effectiveness is addressed by outlining the case of the iritermediary and that of the end-user. Many online users experience difficulties in determining which hosts or databases are the most cost-effective for a given search or service. The variant and constantly-shifting price structures adopted by hosts were at the heart of their problems and made cost benefit calculations particularly difficult.

A Distributed Infrastructure for Earth-Science Big Data Retrieval

Earth-Science data are composite, multi-dimensional and of significant size, and as such, continue to pose a number of ongoing problems regarding their management. With new and diverse information sources emerging as well as rates of generated data continuously increasing, a persistent challenge becomes more pressing: To make the information existing in multiple heterogeneous resources readily available. The widespread use of the XML data-exchange format has enabled the rapid accumulation of semi-structured metadata for Earth-Science data. In this paper, we exploit this popular use of XML and present the means for querying metadata emanating from multiple sources in a succinct and effective way. Thereby, we release the user from the very tedious and time consuming task of examining individual XML descriptions one by one. Our approach, termed Meta-Array Data Search (MAD Search), brings together diverse data sources while enhancing the user-friendliness of the underlying information sources. We gather metadata using different standards and construct an amalgamated service with the help of tools that discover and harvest such metadata; this service facilitates the end-user by offering easy and timely access to all metadata. The main contribution of our work is a novel query language termed xWCPS, that builds on top of two widely-adopted standards: XQuery and the Web Coverage Processing Service (WCPS). xWCPS furnishes a rich set of features regarding the way scientific data can be queried with. Our proposed unified language allows for requesting metadata while also giving processing directives. Consequently, the xWCPS-enabled MAD Search helps in both retrieval and processing of large data sets hosted in an heterogeneous infrastructure. We demonstrate the effectiveness of our approach through diverse use-cases that provide insights into the syntactic power and overall expressiveness of xWCPS. We evaluate MAD Search in a distributed environment that comprises five high-volume array-databases whose sizes range between 20 and 100 GB and so, we ascertain the applicability and potential of our proposal.

A review of research on human‐computer interfaces for online information retrieval systems

Purpose

The purpose of this article is to review the research on human‐computer interfaces for library‐based commercial online information retrieval (IR) systems.

Design/methodology/approach

The review first focuses on basic interface issues for information retrieval such as interface style, end‐user searching, query formulation, relevance feedback and browsing. The second part deals with cognitive engineering in IR including mental models and individual differences. Finally, the topics on user interface engineering are covered. These include user interface guidelines, usability evaluation methods and interface engineering techniques.

Findings

The review shows that user interface design has received a limited attention from IR researchers. There is a need for adopting human‐computer interaction (HCI) techniques into IR interface designs, but this issue has not yet been fully recognised by the commercial database vendors and distributors. The paper recommends that applying HCI techniques could help in developing more usable IR interfaces.

Practical implications

The review identifies the main activities of a user‐centred design methodology and suggests that IR interface designers should use this method in future. This could have major implications in IR interface design for end‐user searching.

Originality/value

The review is the first to offer an overview of empirical research on IR interface design and IR usability engineering. Both IR researchers and practitioners may benefit from the description of previous research and the user‐centred design advocated by the current research.

Query-based sampling of text databases

The proliferation of searchable text databases on corporate networks and the Internet causes a database selection problem for many people. Algorithms such as gGLOSS and CORI can automatically select which text databases to search for a given information need, but only if given a set of resource descriptions that accurately represent the contents of each database. The existing techniques for a acquiring resource descriptions have significant limitations when used in wide-area networks controlled by many parties. This paper presents query-based sampling , a new technicque for acquiring accurate resource descriptions. Query-based sampling does not require the cooperation of resource providers, nor does it require that resource providers use a particular search engine or representation technique. An extensive set of experimental results demonstrates that accurate resource descriptions are crated, that computation and communication costs are reasonable, and that the resource descriptions do in fact enable accurate automatic dtabase selection.

Knowledge-based search tactics for an intelligent intermediary system

Research on the nature of knowledge-based systems for bibliographic information retrieval is summarized. Knowledge-based search tactics are then considered in terms of their role in the functioning of a semantically based search system for bibliographic information retrieval, EP-X. This system uses such tactics to actively assist users in defining or refining their topics of interest. It does so by applying these tactics to a knowledge base describing topics in a particular domain and to a database describing the contents of individual documents in terms of these topics. This paper, then, focuses on the two central concepts behind EP-X: semantically based search and knowledge-based search tactics.

A methodology for user charge estimation in numeric online databanks. Part I: A review of numeric databanks and charging principles

Recent studies on user charging in information retrieval services emphasize charging on the basis of the information retrieved from the databases or its retrieval costs as being more justified and appropriate as bases for charging than the tradi tional connect-time. When these charging bases are apphed in numeric online databanks, the charges vary over a very broad range, depending on factors which the users cannot know or manage. Therefore the users cannot estimate their charges in advance, prior to query execution. This has many undesirable practical consequences on information retrieval and informa tion seeking. In order to avoid such consequences and to achieve full advantage of such charging bases, user charge estimation tools which automatically estimate the charges on the basis of user query statements must be provided in the query systems to databanks. A novel and systematic methodol ogy for user charge estimation, to be applied by the tools, is reviewed. The methodology has been developed in the context of the relational data model. By applying the methodology, user charges for the information retrieved and its retneval costs for relational algebra quenes can be estimated generally, accu rately and conveniently. In addition to the charge estimates, the methodology provides rich descriptions of the query results that essentially support query formulation. Therefore the user can concentrate on query formulation with a clear idea about the query result and his charges in mind. The architecture of the methodology is such that the methodology can be extented to further charging bases in information retneval (e.g. data communication costs). In the article, the state of the art and trends in the development and use of databanks and in the charging principles of information retrieval are first reviewed. The methodology is then descnbed and special attention is paid to the design of user interfaces of the tools based on the methodology.

Observations of end-user online searching behavior over eleven years

End-user searching of National Library of Medicine (NLM) online data bases during eleven years has been investigated through transaction logs, questionnaires, and follow-up interviews. From 1976 through 1984, pathologists and pharmacists performed 8,313 searches. Highlights of our studies are compared with a review of other end-user research. Volume of searching is directly related to the convenient placement of the terminal in the work place. Slightly fewer than half of all potential searchers actually search for themselves. Practices of pharmacists and pathologists do not differ in important ways. Nonmediated searchers feel they need answers more promptly than do those who obtain mediated searches. End-users perform very simple searches, mostly using only the AND operator. Problems with techniques are fewer and more easily solved than those with the vocabulary and content of the system. The major problems, with the most powerful capabilities of MEDLINE--subheadings and explosions--sometimes cause substantial loss of references, but in relatively few searches. One-on-one teaching is most popular, with trial-and-error the most frequent procedure used in actual learning.