Web of Science: The Use & Abuse of Citation Data

Mark Robertson & Adam TavesScott Library

Reference Dept.

What is Citation Data?

• Generated by counting numbers of times publications have been cited

• Allows for the analysis of relationships between publications

• Measure of importance and usage• Another name for this field: Bibliometrics• First proposed by Eugene Garfield in

1955• Garfield founded Institute for Scientific

Information (ISI)

3 Kinds of Citation Data

Articles• Citation Impact

Authors• h-index & g-index

Journals• Journal Impact Factor

Kinds of Citation Data

Counting Articles

Times Cited

Kinds of Citation Data

Measuring Author Impact & Productivity

h-index: a scholar with an index

of h has published h papers with at least h citations each

Kinds of Citation Data

Measuring Journal Quality

Impact Factor

Definition: The average number of times published papers are cited in the two calendar years following publication

Sources of Citation Data

ISI ProductsWeb of Science (ISI)

Journal Citation Reports (ISI)

Other ProductsGoogle Scholar

Scopus

The Uses of Citation Data

By Researchers– To look for research which up-

dates earlier findings– Identify more articles on same

topic– To look for replications of

empirical research– To follow a scholarly debate

through time– To identify significant

publications– Historians examining scholarly

trends

The Uses of Citation Data

Administrative Purposes– Tenure & promotion– Funding / grant

proposals– Deciding where to

publish– Libraries use to make

collection decisions

Demonstrations

Web of Science

Journal Citation Reports

Google Scholar

Publish or Perish

Thinking Critically About Citation Analysis

Is It Comprehensive?

• Excludes citations in books• SCI indexes 5,900 journals• SSCI indexes 1,725 journals• A&HSI indexes 1,144 journals• In 1997 estimated that SCI

covers only 2.5% of world’s scientific journals

Apples & Oranges?

All articles are not the same (review articles vs. case studies)

Disciplinary Cultures: History vs. Immunology

Psychiatry journals

Developmental Psychology journals

Manipulation of Rankings

• Self-citation• Journals publish more

review articles, etc.• Some journals

encourage citation from same journal

• Speeding up publication cycle increases impact factor

The Matthew Effect

• “The rich get richer and poor get poorer”

• A centrifugal effect• High journals rankings are self-

perpetuating• Hard for new journals to break

into high rankings• Anglo-American bias• Non-English language citations

undercounted

What Does It Really Measure?

• Use not quality

• Consider case of Google result rankings