Richard Luce

Toward alternative metrics of journal impact: a comparison of download and citation data

We generated networks of journal relationships from citation and download data, and determined journal impact rankings from these networks using a set of social network centrality metrics. The resulting journal impact rankings were compared to the ISI IF. Results indicate that, although social network metrics and ISI IF rankings deviate moderately for citation-based journal networks, they differ considerably for journal networks derived from download data. We believe the results represent a unique aspect of general journal impact that is not captured by the ISI IF. These results furthermore raise questions regarding the validity of the ISI IF as the sole assessment of journal impact, and suggest the possibility of devising impact metrics based on usage information in general.

Evaluation of Digital Library Impact and User Communities by Analysis of Usage Patterns

At present, digital library (DL) policy is largely informed by management intuition and coarse measures of user satisfaction. Most DLs, however, maintain extensive server logs of user retrieval requests that contain a wealth of information on user preferences and the structure of user retrieval patterns. We propose a quantitative approach to DL evaluation that analyzes the retrieval habits of users to assess the impact of a collection of documents and to determine the structure of a given DL user community. We discuss a system that we have developed to automatically generate extensive journal and document networks from an efficient and simple analysis of user retrieval sequences registered in a particular DLs server logs.

ActiveGraph: A digital library visualization tool

ActiveGraph is an information visualization tool designed to provide users with a concise, customizable view of objects in a digital library. A set of digital library objects is represented as a data set in a two- or three-dimensional scatter plot. The data set can represent any digital library objects in any medium: books, journals, papers, images, Web resources, or even entire databases. Since ActiveGraph is intended for use in the context of digital libraries, data attributes consist for the most part of metadata fields such as title, author, date of publication, and number of citations. Data attributes are mapped to six visual attributes of the scatter plot: the X-, Y-, and Z-axes, color, size, and shape. The metadata for a selected data point are displayed in a control panel on the right-hand side of the screen. Users can edit the metadata and even add new metadata fields. Thus ActiveGraph allows users to both view and customize the contents of a library. Because of its flexibility in handling digital library objects and metadata of different types, ActiveGraph can be used in a variety of digital library applications. In this paper, we describe two: LibGraph, which is a visualization of a collaborative library, and CiteGraph, which is a visualization of citation statistics. Both applications were designed for use by scientists and engineers, for whom scatter plots are familiar and intuitive visualizations.

Usage Analysis for the Identification of Research Trends in Digital Libraries

The analysis of user logs from large-scale digital libraries offers new opportunities to assess research trends in an institutions user communities. We describe the application of a methodology to derive weighted journal relationship networks from reader logs at the Los Alamos National Laboratorys Research Library during 1998 and 2001. A journal impact metric is defined that derives journal impact from the structural features of the generated journal relationship networks, much in the same manner Googles PageRank evaluates the impact of web pages for a given subject on the basis of its context of hyperlinks to other pages. A comparison of this reader impact metric to the ISI Impact Factor values for the same journals in 1998 and 2001 allows us to detect and interpret community-specific research trends where the LANL community deviates from Usage Analysis for the Identification of Research Trends in Digit... http://www.dlib.org/dlib/may03/bollen/05bollen.html 1 of 21 12/9/13 4:02 PM more general trends as indicated by changes in the Institute for Scientific Indexing (ISI) Impact Factors during those same years. Such analysis yields information to aid digital library managers to improve the evaluation of not only which parts of the collection are most highly valued by their local community, but it also detects research trends in user communities as they evolve over time.

MyLibrary at LANL: proximity and semi-metric networks for a collaborative and recommender Web service

We describe a network approach to building recommendation systems for a Web service. We employ two different types of weighted graphs in our analysis and development: proximity graphs, a type of fuzzy graphs based on a co-occurrence probability, and semi-metric distance graphs, which do not observe the triangle inequality of Euclidean distances. Both types of graphs are used to develop intelligent recommendation and collaboration systems for the MyLibrary@LANL Web service, a user-centered front-end to the Los Alamos National Laboratorys digital library collections and Web resources.

ScienceSifter: facilitating activity awareness in collaborative research groups through focused information feeds

As the amount of scientific information available to researchers increases, the challenge of sifting through the information to find what is truly important to their work increases, as well. In this paper we describe ScienceSifter, a tool that addresses this challenge by enabling groups of researchers and channel editors to create and customize information feeds. Using ScienceSifter, users can combine several information feeds, then filter them by keywords to create a focused information feed. They can view the feed in a shared information space in the form of a list, a list with descriptions, or a hyberbolic tree visualization, and they can save items to a shared list. Thus ScienceSifter can reduce the amount of time researchers spend finding and sharing information. It can facilitate shared intellectual activity and activity awareness among the members of the group

Toolkits for visualizing co-authorship graph

Visualization eases insight into complex systems such as coauthorship networks. We present an initial deployment of an author navigator application for convenient visual examination of JCDL and LANL coauthorship networks.

Detecting Research Trends in Digital Library Readership

The research interests and preferences of the reader communities associated to any given digital library may change over the course of years. It is vital for digital library services and collection management to be informed of such changes, and to determine how they may point to future trends. We propose the Impact Discrepancy Ratio metric for the detection of research trends in a large digital library by comparing a reader-defined metric of journal impact to the Institute for Scientific Information Impact Factor (ISI IF) over the course of three years. An analysis for the Los Alamos National Laboratory (LANL) Research Library (RL) comparing reader impact to the ISI IF for 1998 and 2001 indicates journals relating to climatology have undergone a sharp increase in local impact. This evolution pinpoints specific shifts in the local strategies and reader interests of the LANL RL which were qualitatively validated by LANL RL management.

Technical Report Interchange through Synchronized OAI Caches

The Technical Report Interchange project is a cooperative experimental effort between NASA Langley ResearchCen ter, Los Alamos National Laboratory, Air Force Research Laboratory, Sandia National Laboratory and Old Dominion University to allow for the integration of technical reports. This is accomplished using the Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH) and having each site cache the metadata from the other participating sites. Each site also implements additional software to ingest the OAI-PMH harvested meta-data into their native digital library (DL). This allows the users at each site to see an increased technical report collection through the familiar DL interfaces and take advantage of whatever valued added services are provided by the native DL.

The Open Archives initiative : Interoperable, interdisciplinary author self-archiving comes of age

Abstract Author self-archiving systems, emerging from successful experiments with preprint servers, have emerged in a variety of fields. The Open Archives initiative was organized to create a forum to solve interoperability issues between author self-archiving solutions, as a way to promote their global acceptance. The initiative seeks to develop a framework for a “universal e-print archive” that establishes interoperability standards supporting the search and retrieval of e-print papers from all disciplines. The Santa Fe conventions were developed to ensure these archives work together so that any paper in any of these archives can be found from anyones desktop worldwide, as if it were all in one virtual public library.