Average of relative citations (ARC): The ARC is a citation measure normalized across fields of science and years of publication to correct for differences in the frequency and timing of citations. Dividing each publication’s citation count by the average citation count of all publications in that subfield in that same year creates a relative citation. Then, for a given geography or sector, these relative citations for each publication are averaged to create an ARC.

Doctoral academic S&E workforce: Includes those with a research doctorate in science, engineering, or health who are employed in 2- or 4-year colleges or universities, including medical schools and university research institutes, in the following positions: full and associate professors (referred to as senior faculty); assistant professors (referred to as junior faculty); postdoctorates (postdocs); other full-time positions, such as instructors, lecturers, adjunct faculty, research associates, and administrators; and part-time positions of all kinds. Unless otherwise specified, these individuals earned their doctorate at a U.S. university or college.

European Union (EU): The EU comprises 28 member nations: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, and the United Kingdom. Unless otherwise noted, Organisation for Economic Co-operation and Development data on the EU include all 28 nations.

Federally funded research and development center (FFRDC): R&D organization exclusively or substantially financed by the federal government, to meet particular R&D objectives or, in some instances, to provide major facilities at universities for research and associated training purposes. An industrial firm, a university, or a nonprofit institution administers each FFRDC.

Fractional counting: Method of counting S&E publications in which credit for coauthored publications is divided among the collaborating institutions or countries based on the proportion of their participating authors.

Index of highly cited articles: A country’s share of the top 1% most-cited S&E publications divided by the country’s share of all S&E publications. An index greater than 1.00 means that a country contributed a disproportionately larger share of highly cited publications; an index less than 1.00 means a smaller share.

Index of international collaboration: Country A’s rate of coauthorship in country B’s international collaborations, divided by country B’s overall international collaboration rate. Values are symmetrical for country-country pairs. An index greater than 1.00 means that a country-country pair has a stronger-than-expected tendency to collaborate; an index less than 1.00 means a weaker-than-expected tendency to collaborate.

Net assignable square feet (NASF): Unit for measuring research space. NASF is the sum of all areas on all floors of a building assigned to, or available to be assigned to, an occupant for a specific use, such as research or instruction. NASF is measured from the inside face of walls.

Relative citation index: Country A’s share of citations to country B’s S&E publications divided by total citations to country B’s S&E publications. An index of greater than 1.00 means that the country has a higher-than-expected tendency to cite the other country’s S&E literature; an index less than 1.00 means a lower-than-expected tendency to cite the other country’s literature.

Research space: The budgeted and accounted-for space used for sponsored R&D activities at academic institutions. Research space is the net assignable square feet of space in buildings within which research activities take place. Research facilities are located within buildings. A building is a roofed structure for permanent or temporary shelter of people, animals, plants, materials, or equipment. Structures are included as research space if they are (1) attached to a foundation; (2) roofed; (3) serviced by a utility, exclusive of lighting; and (4) a source of significant maintenance and repair activities.

Underrepresented minority: Racial and ethnic groups, including blacks, Hispanics, and American Indians or Alaska Natives, which are considered to be underrepresented in academic S&E employment.

Key to Acronyms and Abbreviations

ADEA: Age Discrimination in Employment Act of 1967

ARC: average of relative citations

ARRA: American Recovery and Reinvestment Act

DOAJ: Directory of Open Access Journals

DOD: Department of Defense

DOE: Department of Energy

EPA: Environmental Protection Agency

EPSCoR: Established Program to Stimulate Competitive Research

EU: European Union

FFRDC: federally funded research and development center

FY: fiscal year

HERD: Higher Education Research and Development Survey

HHS: Department of Health and Human Services

HPC: high-performance computing

NASA: National Aeronautics and Space Administration

NASF: net assignable square feet

NCSES: National Center for Science and Engineering Statistics

nec: not elsewhere classified

NIH: National Institutes of Health

NSCG: National Survey of College Graduates

NSCI: National Strategic Computing Initiative

NSF: National Science Foundation

OA: open access

R&D: research and development

RC: relative citation

S&E: science and engineering

SciELO: Scientific Electronic Library Online

SDR: Survey of Doctorate Recipients

UK: United Kingdom

URM: underrepresented minority (black or African American, Hispanic or Latino, and American Indian or Alaska Native)

USDA: Department of Agriculture

WebCASPAR: Integrated Science and Engineering Resources Data System

XSEDE: Extreme Science and Engineering Discovery Environment