Citation Indexing ISI Web of Science and Journal Citation Reports Tracy Matthews Thomson Scientific Tracy.matthews@thomson.com

So, What is a Citation Index? In addition to standard bibliographic information a citation index includes the cited references of the items indexed. An author implies a subject relationship when he or she cites a work: “the act of citing is an expression of the importance of the material.” References serve to essentially replace a controlled vocabulary Other terms for Cited References are: reference list, works cited, bibliography. Dr. Garfield goes on to explain “The total number of expressions [citations] is about the most objective measure there is of the materials importance to current research.” Concept of a citation index to the scientific literature, according to Dr. Garfield, developed from “bits and pieces of experience and insight accumulated over a period of a few years.” In addition to his work with the Welch Medical Library Project: Chemical Abstracts (voluntary abstract work for CA) utility of abstracts increases by including references to abstracts of key papers cited by the authors Special Study of Review Articles Provide scientists with guideposts to the literature. Noted that nearly every sentence in a review article is supported by a citation and that that sentence provided a pithy abstract of the cited work itself Shepard’s Citations (next slide)

Things to Keep in Mind . . . Authors cite works both to support and to refute them. There are no codes in the ISI database to tell you why an item is cited. ISI Cited References are not an attempt to re-create a bibliography word for word. 1st listed author’s surname & up to 3 initials Abbreviated title of the cited work Volume, starting page, and cited year. Remember that citations are captured as cited. Some disciplines have between a 10-25 % citation error rate. ISI’s citation error rate is lower because many citation errors are unified with the correct citation automatically.

ISI Citation Indexes Bibliography entry: ISI Cited Reference: Wheatley A & Armstrong C. (1997). Metadata, recall, and abstracts: can abstracts ever be reliable indicators of document value? ASLIB Proceedings 49 (8): 206-213. ISI Cited Reference: WHEATLEY A ASLIB PROC 49 206 1997 Note that only the first listed author is included in the cited reference, along with an abbreviation for the journal title.

Shepardizing In 1953 Dr. Garfield learns of Shepard’s Citations Developed in 1873, the oldest major citation index in existence American legal system is based on precedent Shepard’s lists the citations to precedents used in cases decided by the courts and federal administrative agencies Provides a model for how a citation index could be organized into an effective search tool Garfield was not the first to create a citation index. Shepard’s is a “case citator”: document changes in legal effect of court cases identify any subsequent legal action that may have reversed or overruled an earlier decision. Science is also based on precedent

Welch Medical Library Project Dr. Garfield becomes interested in machine generated term indexing: generate terms that effectively describe the “aboutness” of a document do this without the need of intellectual judgements from human indexers From this interest . . . citation indexing. The citation index, according to Garfield would eliminate this need for the intellectual judgements of human indexers save time save money decrease subjective and often inconsistent judgments made by human indexers

Pilot Citation Indexes ISI produces the 1961 Genetics Citation Index with a grant from the National Institutes of Health Compile a comprehensive, multidisciplinary database Extract relevant genetics material Provided a more comprehensive, deeper view of the literature than conventional subject indexes. Original comprehensive database consisted of citations of all the material published in 1961 by the 600 journals covered by Current Contents and of all the references in that material. The source journals included both general works--such as Science and Nature--and specialized journals from a range of disciplines.

Pilot Citation Indexes The multidisciplinary index provided several distinct advantages: Illuminated the bounds of a particular discipline Insights into patterns of scholarly communication and journal networks Revealed the historical development of scientific thought Indicated the implications and impact of a particular work They found that the advantages of the index increased as they went from narrow (genetics) to broad (multidisciplinary).

ISI Citation Indexes ISI’s findings compelled them to create the Science Citation Index. The Social Sciences Index followed in 1973. The Arts & Humanities Index was introduced in 1978. ISI published the SCI after the government rejected the recommendation to create a broad, multidisciplinary database.

Benefits of a Citation Index Allows searching forward in time. Take a known paper and find out who is citing it. Classification terms in subject indexes can be ambiguous. Citations are bound to concepts instead of vocabulary. Put a work in context. What progress has been made in that area since the work’s publication? Also use a citation index to find: Has a basic concept been applied elsewhere? Has a theory been confirmed or refuted? Have there been any correction notes published?

Benefits of a Citation Index Multidisciplinary Citation Indices allow for serendipitous discovery A subject-specific index might not have index terms for each concept in a given article. Ex. Space debris Use a relevant current events topic to illustrate this point. Try a science topic with a geopolitical aspect. (A chemistry index would not necessarily be able to capture the political policy aspects of an article on global warming and greenhouse gas emission standards.)

Uses of Citation Analysis Researcher evaluation Use as a starting point in promotion and tenure decisions. Competitive intelligence Find out what competitors are publishing and citing. Mapping relationships between subject areas Bibliometric researchers determine relationships between disciplines. Editors may use it to determine their competitive position Information scientists interested in studying the structure of the literature Librarians managing journal collections Researchers needing to identify useful journals outside of her or his own subject area Also: find out what impact a particular researcher or scholar has on a field of study.

Macro Citation Analysis JCR Impact Factor How often is the typical article from a specific journal cited? Institutional Journal Use Analysis Selection, retention, archiving, and storage decisions Which journals are the faculty at your institution using the most? Data from citation indexes aggregated in the Journal Citation Reports Can be used as a factor in journal evaluation From the data a variety of measurments are created Most important is the impact factor Certain types of journals are more or less cited than others review journals v. more news-oriented journals Certain disciplines may have higher impact factors genetics v. chemical engineering with an IF of 2.0

Publication Selection

Database Production and Extraction ISI Database Journal/Book acquisition Item Selection and Data Capture Manual Indexing/ Translation (for foreign language journals and some A&H content) Processing Time 1-2 Weeks Appearance of item in ISI’s products Scanning & OCR

Document Types All Files Arts & Humanities Only Article Bibliography Biographical Item Book Review Correction Database Review Editorial Material Hardware Review Letter Meeting Abstract News Item Reprint Review Software Review Arts & Humanities Only Art Exhibit Review Dance Performance Review Excerpt Fiction Creative Prose Film Review Music Performance Review Music Score Music Score Review Poetry Record Review Script Theater Review TV Review Radio Review

New Cited References Weekly Journal Coverage Covered Journals New Records Weekly New Cited References Weekly Science Citation Index Expanded 6,034 18,800 431,000 Social Sciences Citation Index 1,764 2.600 59,100 Arts & Humanities Citation Index 1,121 2,100 15,900

Full Bibliographic Record All author names are indexed and searchable. ISI indexes an author’s complete last name and up to five initials. The complete abstract is indexed and searchable.

Full Bibliographic Record (continued) Author Keywords are indexed when included with the published item. KeyWords Plus are harvested from the titles of the cited articles. Author affiliations are indexed when available with the published item. The reprint author’s address is listed as the first address in the field.

Full Record / Elements Author name All authors indexed and searchable – last name and up to 5 initials Title Complete article title as published. Non-English titles translated into US English Source Information Journal title, Volume, Issue, Page Range, Date Abstract Full author abstract Author Keywords When included in original publication KeyWords Plus Selected from titles of cited references Address Author affiliations are captured when provided. First line of address field lists reprint author address

Cited References Cited References in blue are links to full records. (Limited by your subscribed data years.)

Cited References (continued) Cited References in plain text are citations to items outside of your coverage; to items ISI doesn’t index (books, etc.); or to items that have been cited incorrectly by the author (cited reference variants.)

Cited Reference Components

Cited Reference Components (continued)

* ? $ Truncation Symbol Retrieves Zero or more characters Zero or one character ? One character only

Boolean Operators All search terms must occur to be retrieved. TOPIC: aspartame AND cancer* Retrieves documents that contain both aspartame and cancer*. Any one of the search terms must occur to be retrieved. Use when searching variants and synonyms. TOPIC: aspartame OR saccharine OR sweetener* Retrieves documents that contain at least one of the terms. Excludes records that contain a given search term. TOPIC: aids NOT hearing Retrieves documents with aids, excluding any which also contain hearing.

Proximity Operators Implied Adjacency By default, searching a phrase retrieves records that contain the adjacent terms in the same order. Same Terms must occur within the same sentence, where “sentence” is generally a period-delimited string, in any order. In keyword fields, the SAME operator will retrieve records with search terms in the same keyword phrase.