Editing CiteSeerX (section)

=== CiteSeer and CiteSeer.IST ===
CiteSeer was created by researchers [[Lee Giles]], [[Kurt Bollacker]] and [[Steve Lawrence (computer scientist)|Steve Lawrence]] in 1997 while they were at the [[NEC Research Institute]] (now [[NEC Laboratories America|NEC Labs]]), [[Princeton, New Jersey]], US. CiteSeer's goal was to actively crawl and harvest academic and scientific documents on the web and use autonomous [[citation index]]ing to permit querying by citation or by document, ranking them by [[citation impact]]. At one point, it was called ResearchIndex.

CiteSeer became public in 1998 and had many new features unavailable in academic search engines at that time. These included:
* Autonomous Citation Indexing automatically created a citation index that can be used for literature search and evaluation.
* Citation statistics and related documents were computed for all articles cited in the database, not just the indexed articles.
* Reference linking, allowing browsing of the database using citation links.
* Citation context showed the context of citations to a given paper, allowing a researcher to quickly and easily see what other researchers have to say about an article of interest.
* Related documents were shown using citation and word based measures, and an active and continuously updated bibliography is shown for each document.

CiteSeer was granted a United States [[patent]] #&nbsp;6289342, titled "''Autonomous citation indexing and literature browsing using citation context''", on September 11, 2001. The patent was filed on May 20, 1998, and has priority to January 5, 1998. A continuation patent (US Patent #&nbsp;6738780) was filed on May 16, 2001, and granted on May 18, 2004.{{Citation needed|date=April 2023}}

After NEC, in 2004 it was hosted as CiteSeer.IST on the [[World Wide Web]] at the College of Information Sciences and Technology, The [[Pennsylvania State University]], and had over 700,000 documents. For enhanced access, performance and research, similar versions of CiteSeer were supported at universities such as the [[Massachusetts Institute of Technology]], [[University of Zürich]] and the [[National University of Singapore]]. However, these versions of CiteSeer proved difficult to maintain and are no longer available. Because CiteSeer only indexes freely available papers on the web and does not have access to publisher metadata, it returns fewer citation counts than sites, such as [[Google Scholar]], that have publisher metadata.
<!-- for historical reference:
Versions of CiteSeer have been or are available at the following links:
* [https://citeseer.ittc.ku.edu/ Univ. of Kansas]
* [https://citeseer.csail.mit.edu/ MIT]
* [https://sherry.ifi.unizh.ch/ Univ. of Zürich]
* [https://citeseer.comp.nus.edu.sg/cs National Univ. of Singapore]

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CiteSeer had not been comprehensively updated since 2005 due to limitations in its architecture design. It had a representative sampling of research documents in computer and information science but was limited in coverage because it was limited to papers that are publicly available, usually at an author's homepage, or those submitted by an author. To overcome some of these limitations, a modular and open source architecture for CiteSeer was designed – CiteSeer<sup>X</sup>.