Edwin A. Henneken

The effect of use and access on citations

It has been shown (Lawrence, S. (2001). Online or invisible? Nature, 411, 521) that journal articles which have been posted without charge on the internet are more heavily cited than those which have not been. Using data from the NASA Astrophysics Data System (ads.harvard.edu) and from the ArXiv e-print archive at Cornell University (arXiv.org) we examine the causes of this effect.

Effect of E-printing on Citation Rates in Astronomy and Physics

In this report we examine the change in citation behavior since the introduction of the arXiv e-print repository (Ginsparg, 2001). It has been observed that papers that initially appear as arXiv e-prints get cited more than papers that do not (Lawrence, 2001; Brody et al., 2004; Schwarz & Kennicutt, 2004; Kurtz et al., 2005a, Metcalfe, 2005). Using the citation statistics from the NASA-Smithsonian Astrophysics Data System (ADS; Kurtz et al., 1993, 2000), we confirm the findings from other studies, we examine the average citation rate to e-printed papers in the Astrophysical Journal, and we show that for a number of major astronomy and physics journals the most important papers are submitted to the arXiv e-print repository first.

E-prints and journal articles in astronomy : a productive co-existence

Are the e‐prints (electronic preprints) from the arXiv repository being used instead of journal articles? We show that the e‐prints have not undermined the usage of journal papers from the four core journals in astrophysics. As soon as the journal article is published, the astronomical community prefers to read it and the use of e‐prints through the NASA Astrophysics Data System drops to zero. This suggests that most astronomers have access to institutional subscriptions and that they choose to read the journal article. In other words, the e‐prints have not undermined journal use in this community and thus currently do not pose a financial threat to publishers. Furthermore, we show that the half‐life (the point at which the use of an article drops to half the use of a newly published article) for an e‐print is shorter than for a journal paper.

Use of astronomical literature—A report on usage patterns

In this paper we present a number of metrics for usage of the SAO/NASA Astrophysics Data System (ADS). Since the ADS is used by the entire astronomical community, these are indicative of how the astronomical literature is used. We will show how the use of the ADS has changed both quantitatively and qualitatively. We will also show that different types of users access the system in different ways. Finally, we show how use of the ADS has evolved over the years in various regions of the world.

Measuring metrics - a 40-year longitudinal cross-validation of citations, downloads, and peer review in astrophysics

Citation measures, and newer altmetric measures such as downloads are now commonly used to inform personnel decisions. How well do or can these measures measure or predict the past, current, or future scholarly performance of an individual? Using data from the Smithsonian/NASA Astrophysics Data System we analyze the publication, citation, download, and distinction histories of a cohort of 922 individuals who received a U.S. PhD in astronomy in the period 1972‐1976. By examining the same and different measures at the same and different times for the same individuals we are able to show the capabilities and limitations of each measure. Because the distributions are lognormal, measurement uncertainties are multiplicative; we show that in order to state with 95% confidence that one persons citations and downloads are significantly higher than another persons, the log difference in the ratio of counts must be at least 0.3dex, which corresponds to a multiplicative factor of 2.

Finding Your Literature Match – A Recommender System

The universe of potentially interesting, searchable literature is expanding continuously. Besides the normal expansion, there is an additional influx of literature because of interdisciplinary boundaries becoming more and more diffuse. Hence, the need for accurate, efficient and intelligent search tools is bigger than ever. Even with a sophisticated search engine, looking for information can still result in overwhelming results. An overload of information has the intrinsic danger of scaring visitors away, and any organization, for-profit or not-for-profit, in the business of providing scholarly information wants to capture and keep the attention of its target audience. Publishers and search engine engineers alike will benefit from a service that is able to provide visitors with recommendations that closely meet their interests. Providing visitors with special deals, new options and highlights may be interesting to a certain degree, but what makes more sense (especially from a commercial point of view) than to let visitors do most of the work by the mere action of making choices? Hiring psychics is not an option, so a technological solution is needed to recommend items that a visitor is likely to be looking for. In this presentation we will introduce such a solution and argue that it is practically feasible to incorporate this approach into a useful addition to any information retrieval system with enough usage.

How the Literature is Used A View Through Citation and Usage Statistics of the ADS

The data holdings, usage and citation records of the NASA Astrophysics Data System (ADS) form a unique environment for bibliometric studies. Here we will highlight one such study. Using the citation and usage statistics from the NASA Astrophysics Data System, we study the impact of offering a paper as an electronic pre-print (“e-print”) on the arXiv e-print repository, prior to its publication in a scholarly journal. We will address the following questions for astronomy: are people reading the e-prints from arXiv instead of the journal articles? Are e-prints read in a different way than journal articles? What is the impact of offering a paper as e-print prior to its publication in a scholarly journal? We will show that in astronomy, the e-prints are not being read instead of the journal article. As soon as the journal article is published, users prefer to read the article. Our analysis confirms that journal articles which were submitted as e-print on arXiv, prior to their publication, show higher citation rates than journal articles that were not submitted as e-print.

New ADS Functionality for the Curator

In this paper we provide an update concerning the operations of the NASA Astrophysics Data System (ADS), its services and user interface, and the content currently indexed in its database. As the primary information system used by researchers in Astronomy, the ADS aims to provide a comprehensive index of all scholarly resources appearing in the literature. With the current effort in our community to support data and software citations, we discuss what steps the ADS is taking to provide the needed infrastructurein collaboration with publishers and data providers. A new API provides accessto the ADS search interface, metrics, and libraries allowing users to programmatically automate discovery and curation tasks. The new ADS interface supports a greater integration of content and services with a variety of partners, including ORCID claiming, indexing of SIMBAD objects, and article graphics from a variety of publishers. Finally, we highlight how librarians can facilitate the ingest of gray literature that they curate into our system.

Linking scholarly literature to research data and software - lessons learned in astronomy: Linking Scholarly Literature to Research Data and Software - Lessons Learned in Astronomy

Publishing articles in scholarly journals is essential to furthering science. However, it is only one stage in the research cycle; one of the later stages, actually. After formulating a research goal, typically one or more proposals are written. When accepted, data is gathered, processed and compared to existing data and literature. Software plays an essential role in the data processing and comparison process. Often, before articles are published, papers and posters are presented at conferences. In short, there is a plethora of “products” associated with the entire research lifecycle. An essential ingredient in this cycle is the ability to find literature and associated products that were used to create it. Reproducibility of and the ability to add to existing results should be the norm, not the exception, for robust scientific research. Discoverability of data products and software needs an infrastructure and a culture. Astronomy has a long tradition of sharing data, but there is still a lot of work to do. Having this infrastructure will not only support discoverability, it will also enable measurement of impact and proper attribution. Both elements will help in getting funding for future research, which completes the cycle.

ADS: the Next Generation Search Platform

Four years after the last LISA meeting, the NASA Astrophysics Data System (ADS) finds itself in the middle of major changes to the infrastructure and contents of its database. In this paper we highlight a number of features of great importance to librarians and discuss the additional functionality that we are currently developing. Starting in 2011, the ADS started to systematically collect, parse and index full-text documents for all the major publications in Physics and Astronomy as well as many smaller Astronomy journals and arXiv e-prints, for a total of over 3.5 million papers. Our citation coverage has doubled since 2010 and now consists of over 70 million citations. We are normalizing the affiliation information in our records and, in collaboration with the CfA library and NASA, we have started collecting and linking funding sources with papers in our system. At the same time, we are undergoing major technology changes in the ADS platform which affect all aspects of the system and its operations. We have rolled out and are now enhancing a new high-performance search engine capable of performing full-text as well as metadata searches using an intuitive query language which supports fielded, unfielded and functional searches. We are currently able to index acknowledgments, affiliations, citations, funding sources, and to the extent that these metadata are available to us they are now searchable under our new platform. The ADS private library system is being enhanced to support reading groups, collaborative editing of lists of papers, tagging, and a variety of privacy settings when managing ones paper collection. While this effort is still ongoing, some of its benefits are already available through the ADS Labs user interface and API at this http URL