Chapter 2 of this volume discusses the human capital outputs of higher education in S&E. This section of the current chapter continues that theme by examining the intellectual output of S&E research. The section presents indicators derived from both published research articles and U.S. patents.
Researchers have traditionally published the results of their work in the world’s peer-reviewed S&E journals. These bibliometric data (see sidebar, “Bibliometric Data and Terminology”) are indicators of national and global scientific activity. For example, a count of the coauthorships on U.S. articles is an indicator of the partnerships involved in the U.S. scientific effort. Likewise, measures involving citations and patents can be indicators of international patterns of influence and of invention based on scientific research. Bibliometric indicators are calculated for different countries and—within the United States alone—for different sectors.
Overall, the indicators provide insight into five broad areas. The first section, “S&E Article Output,” examines the quantity and national origin of S&E publications. The second section, “Coauthorship and Collaboration in S&E Literature,” examines the national partnerships in these publications. The third section, “Trends in Citation of S&E Articles,” examines various patterns of national scientific sharing and influence. The fourth section, “Citation of S&E Articles by USPTO Patents,” examines the utilization of S&E literature by inventors. And, finally, the fifth section, “Academic Patenting,” examines patenting and related activities in academia.
Discussions of regional and country indicators will examine patterns and trends in developed and developing countries, as classified by the World Bank. Countries classified by the World Bank as high income are considered developed; those classified as upper- and lower-middle income and as low income are considered developing.
This section begins by describing and comparing the S&E article output of the United States to other regions, countries, and economies in the world. The article output of China and other developing countries has increased much more rapidly than that of the United States and other developed countries over the last 15 years. Although the United States remains a major producer of S&E articles, its global share of article production has declined. This section then examines U.S. article output in academia, the largest producer of U.S. articles, and other institutional sectors.
The four major producers of the world’s S&E articles in 2011 were the European Union (EU; see “Glossary” for member countries) (31%), the United States (26%), China (11%), and Japan (6%). Together, they accounted for 73% of the world’s S&E publications in 2011 (figure
Between 2001 and 2011, the total world S&E article output grew at an average annual rate of 2.8% (table
Among other larger emerging economies, over the decade Brazil grew at a 6.4% average annual rate and India grew at a 7.6% average annual rate, resulting in their global shares increasing 1 percentage point to reach 2% and 3%, respectively (table
Smaller developing countries with rapid S&E article growth (11%–23% annual average) included Iran, Malaysia, Pakistan, Thailand, and Tunisia.
Developed economies’ S&E article production grew more slowly (1.5%) than that of developing economies (9.9%) over the decade. U.S. growth in S&E article production was even slower (1.1%) than the average for all developed economies. The U.S. global share fell from 30% to 26%, mostly as a result of developing economies’ more rapid growth.
The EU, the world’s largest producer, grew slightly more slowly (1.4%) than all developed countries. Among EU member countries, growth rates were slower for the three largest—France, Germany, and the United Kingdom—and generally much faster in Ireland, Portugal, and other smaller member countries. Although EU article production grew slightly faster than that of the United States, the EU’s global share fell from 35% to 31% because of far more rapid growth of developing countries.
S&E article production of Japan, the fourth-largest producer, contracted (-1.7% annual average) over the decade. As a result, Japan’s global share dropped from 9% to 6%, a far greater decline (35%) compared to the declines of the shares of the United States and the EU (15% and 12%). The weakening of Japan’s position may reflect its lengthy economic stagnation despite recent increases in R&D expenditures and reform of its research universities. Also among major developed nations, Russia saw its S&E article output decline (-1.0% annual average) over the decade.
Publication output by developed economies outside of the EU, the United States, and Japan grew much faster, primarily due to rapid growth (6%–9% annual average) in three Asian locations—South Korea, Taiwan, and Singapore.
The distribution of S&E article output by field provides an indication of the priority and emphasis of scientific research in different locations. The S&E article portfolios of the four major producers—the EU, the United States, China, and Japan—have distinct differences (table
Like the United States, the EU is also focused primarily on biological sciences and medical sciences. However, the EU has placed a greater emphasis than the United States on physics, chemistry, and engineering.
Japan’s articles are fairly evenly divided among biological sciences, medical sciences, chemistry, and physics.
China’s S&E portfolio is dominated by chemistry, physics, and engineering, with a far higher concentration in these fields than the three other major producers and most other countries. These fields largely fueled China’s rapid growth in article output. Compared to the rest of the world, China and Japan put very little emphasis on publication in other life sciences, psychology, and social sciences.
Six U.S. institutional sectors produce S&E articles: the federal government, industry, academia, FFRDCs, private nonprofit organizations, and state and local governments. This section describes patterns and trends in the sector distributions of U.S. article output.
The U.S. academic sector is the largest producer of S&E articles, accounting for three-fourths of U.S. S&E article output. This sector was largely responsible for the slight growth of U.S. S&E article output over the last 15 years. The number of academic S&E articles rose from 138,000 to 163,000 between 1997 and 2012. As a result, academia’s share of all U.S. articles rose from 73% to 76% (figure
S&E publications in the non-academic sectors decreased slightly from 52,000 to 51,000 during this period. These sectors had divergent trends:
Except for the FFRDCs, the research portfolios of the U.S. sectors are dominated by life sciences (biological sciences and medical sciences), with nearly half or more of all articles in these fields (table
Collaborative S&E research facilitates knowledge transfer and sharing among individuals, institutions, and nations. It can be an indicator of interconnections among researchers in different institutional settings and the growing capacity of researchers to address complex problems by drawing on diverse skills and perspectives. Collaboration on S&E research publications over the last 15 years has been increasing, with higher shares of scientific articles with more than one named author and a higher proportion of articles with institutional and international coauthorships (figure
The following two sections explore the growth of collaborative publication. The first section looks at international collaboration. The second section examines collaboration across institutional sectors—including academia, the federal government, and industry—within the United States. (Data on sectors for other countries are not available.)
International scientific collaborations reflect wider patterns of relationships among countries. Linguistic and historical factors (Narin, Stevens, and Whitlow 1991), geography, and cultural relations (Glänzel and Schubert 2005) play a role in these relationships. In recent years, coauthorships in Europe have risen in response to EU policies actively encouraging intra-European, cross-border collaboration. Strong ties among science establishments in Asia, though without the formal framework that characterizes Europe, have led to similar collaboration.
Rates of international collaboration by field. Inter-national collaboration on scientific articles, as measured by the shares of articles coauthored by institutional authors in different countries, has increased markedly over the last 15 years. S&E articles with coauthors from more than one country have grown to nearly one-fourth of the world’s S&E articles, rising from 16% in 1997 to 25% in 2012. This is a slightly larger increase than the increase in purely domestic coauthorships during the same period (from 36% to 44%) (figure
Researchers in different fields have different tendencies to collaborate internationally. Astronomy is the most international field, with over half of its articles internationally coauthored (56%) (figure
International collaboration has risen across all scientific fields over the last 15 years. The two fields with the highest rates of international collaboration—astronomy and geosciences—had increases of 17 and 14 percentage points, respectively, in their shares between 1997 and 2012. Physics and chemistry had far lower gains of just 5 and 7 percentage points, respectively. Psychology and other life sciences had strong gains yet remain among the four fields with the least amount of international collaboration.
Rates of international collaboration by country/region. Countries vary widely in the proportion of their S&E articles that are internationally coauthored, ranging from 25% (Iran) to as much as 80% (Saudi Arabia) for articles in 2012 (appendix table
The U.S. international collaboration rate was 35% in 2012, significantly lower than France, Germany, and the United Kingdom (figure
The higher international collaboration rates of large EU member countries relative to the United States are likely due to their smaller science establishments, which increase the need for collaboration teams with international participation. In addition, the EU’s Framework Programmes for Research and Technological Development and other programs designed to increase collaboration among EU member countries and with other countries likely boost their international collaboration.
Japan and China have even lower international collaboration shares than the United States (figure
Rates of international collaboration have generally risen over the last decade, though to varying degrees (figure
The increase has been even more dramatic for EU members and other European countries. The shares of France, Germany, and the United Kingdom increased by 12–16 percentage points to reach over 50%. The EU’s Framework Programmes for Research and Technological Development, now in their seventh year, have likely been a major factor in these countries’ increases.
China is an exception to the general trend of increasing international collaboration. China’s rate of international collaboration (27%) remained stable over the last decade during China’s period of very rapid article growth. In contrast, Chinese domestic collaboration increased in this period: the proportion of its articles that had multiple domestic institutional authors rose by 11 percentage points, reaching 44% (appendix table
Preferred collaboration partners. Different countries have different preferred partners for international scientific collaboration. The remainder of this section describes global partnership patterns, with particular emphasis on patterns of U.S. involvement in international collaboration.
The nation that most often coauthors with the United States is China, a collaborator on 16% of U.S. internationally coauthored articles (table
For most countries, the percentage of U.S. internationally coauthored papers on which they are coauthors has stayed stable over the decade. China and Japan are exceptions. China’s share of U.S. internationally authored articles tripled from 5% in 2002 to 16% in 2012, coinciding with its rapid expansion of article production. China swiftly moved up from the sixth-largest collaborating country in 2005 to the second-largest collaborating country in 2010 before becoming the largest in 2011. Japan’s share of U.S. coauthored articles dropped from 10% to 7%, coinciding with its decline in article production.
Several countries that collaborate on relatively few U.S. internationally coauthored articles have very high U.S. participation in their own internationally coauthored articles. Three economies—Israel, South Korea, and Taiwan—have more than 50% of their international articles coauthored with the United States. Other countries with relatively large U.S. shares of their internationally coauthored articles include Mexico, Chile, Brazil, and Turkey.
An index of international collaboration is useful for highlighting rates of international scientific collaboration that differ substantially from chance (see sidebar, “Normalizing Coauthorship and Citation Data”). When collaborative authorship between two countries is exactly proportional to their overall rates of international collaborative authorship, the index value is 1; a higher index value means that a country pair has a stronger-than-expected tendency to collaborate, and a lower index value means the opposite.
U.S. collaboration with countries as measured by the index of international collaboration shows variable trends (table
In scientific collaboration with EU member countries, the United States has a weaker-than-expected tendency to collaborate with the United Kingdom, Germany, and France despite a comparatively high volume of internationally coauthored articles. U.S. collaboration with these countries became slightly stronger between 1997 and 2012.
In contrast to EU member countries, U.S. collaboration with Asia has generally been stronger than expected. U.S. collaboration is relatively strong with China, South Korea, and Taiwan. However, U.S. collaboration with Japan is slightly weaker than expected despite a high volume of coauthored papers. Between 1997 and 2012, U.S.-Japan collaboration has shifted from as expected to weaker than expected.
Collaborations between Latin American countries are notably stronger than expected. The collaboration index of Mexico-Argentina is 3.88, far above expected levels. The collaboration index of Argentina-Brazil is even higher, at 5.81, one of the highest in the world, and was high, at 4.94, even 15 years ago.
Among European countries, collaboration patterns are mixed, but most have increased between 1997 and 2012. Among the large publishing countries (Germany, the United Kingdom, and France), collaboration was less than expected in 1997 but grew to just about what would be expected in 2012. A particularly strong collaboration network has developed between scientists in Poland and the Czech Republic, with the index for their countries standing at 5.97 in 2012.
The Scandinavian countries increased their collaboration indexes with many countries elsewhere in Europe over the last 15 years (appendix table
Collaboration indexes within Asia and across the South Pacific between the large article producers are generally higher than expected, but some have declined between 1997 and 2012. The collaboration index of China-Japan declined from 1.61 to 1.23; the South Korea–Japan index fell from 2.20 to 1.93. The Australia–New Zealand collaboration index, although much higher than expected, fell from 4.33 to 3.65. Other partnerships strengthened during this period. The Australia-China collaboration shifted from slightly weaker to slightly stronger than expected. India’s collaborations with both South Korea and Japan grew stronger between 1997 and 2012.
U.S. coauthorship data at the sector level—academic, nonprofit, industry, FFRDCs, federal and state government—are indicators of collaboration among U.S. sectors and between U.S. sectors and foreign institutions. The academic sector, the largest article producer among U.S. sectors, is the center of U.S. sector and foreign collaboration. In 2012, the academic sector published 119,371 articles coauthored with other U.S. sectors and foreign institutions, three and a half times more than the 33,973 such articles published by the nonprofit sector, the second largest (table
Although the largest producer of articles coauthored with other U.S. sectors and foreign institutions, academia has the lowest coauthored share of total articles, compared to other U.S. sectors.
Over the last decade, collaboration with other U.S. sectors and with foreign institutions increased strongly in almost all sectors (table
The nonprofit sector had the largest increase in the number of coauthored articles with other U.S. sectors and foreign institutions (from 20,703 to 33,973, a 64% increase). Nonprofit articles coauthored with foreign institutions led the increase, more than doubling (from 6,337 to 13,740). The percentage of articles coauthored with foreign institutions increased their share from 22% to 34%.
Articles with at least one author from industry grew the least over the time period, less than 8%, and in turn had the smallest increase in articles coauthored with other U.S. sectors and foreign institutions (25%).
Much of the growth of industry-coauthored articles was with foreign institutions; foreign coauthorships increased by 57%. Articles coauthored with the academic sector rose by only 29%, the smallest increase among sectors coauthoring with academia.
Citations indicate influence, and they are increasingly international in scope. When scientists and engineers cite the published papers resulting from prior S&E research, they are formally crediting the influence of that research on their own work.
Citations are generally increasing with the volume of S&E articles. (For the analysis of citations from articles to articles, citation counts are limited to a fixed 3-year citation window that begins 4 years and ends 2 years prior to the year of the citing article.) As cited by 1992 articles, an earlier S&E article received, on average, 1.85 citations. In contrast, an S&E article cited by 2012 articles received, on average, 2.47 citations (figure
The next sections examine two aspects of article citations in a global context: the overall rate of citation of a country’s scientific publications, and the share of the world’s most highly cited literature authored by different countries. The discussion of article citations will conclude with an examination of citations to articles authored by researchers at U.S. academic institutions and in other U.S. sectors.
Like the indicators of international coauthorship discussed earlier, cross-national citations are evidence that S&E research is increasingly international in scope. Citations to a country’s articles that come from articles authored outside that country are referred to as international citations. Between 1992 and 2012, the international share of citations increased in all but one of the world’s major S&E article–producing countries.
China is the exception. In 1992, 69% of citations to Chinese S&E articles came from outside China; by 2012, the proportion had dropped to 49% (figure
The relative citation index normalizes cross-national citation data for variations in publication output, much like the collaboration index (see sidebar, “Normalizing Coauthorship and Citation Data”). The expected value is 1.0, but unlike the collaboration index, citation indexes are not symmetric. When country A cites an article by country B, this does not mean that country B is also citing an article by country A. Table
These data indicate the strong influence that geographic, cultural, and language ties have on citation patterns.
U.S. articles are more influential than those produced by the world’s other major publishing regions or countries. They receive 31% more citations than expected. U.S. index values for physics and chemistry are especially high, at 1.49 and 1.43, respectively, but in every field, U.S. articles are disproportionately cited (see figure
Another indicator of the performance of a national or regional S&E system is the share of its articles that are highly cited. High citation rates generally indicate that an article has a relatively great impact on subsequent research.
World citations to U.S. research articles show that, in all broad fields of S&E, U.S. articles continue to have the highest citation rates. In both 2002 and 2012, as displayed in appendix table
U.S. publications uniquely display the preferred citation pattern: the higher the citation percentile, the higher the share of U.S. articles in the citation percentile. In contrast, EU articles are found disproportionately in the middle citation percentiles, while Chinese and Japanese articles are found disproportionately in the lower citation percentiles (see appendix table
Between 2002 and 2012, 1.6%–1.8% of U.S.-authored S&E articles have appeared in the world’s top 1% of cited articles, compared with 0.7%–0.9% of articles from the EU (figure
The high citation of U.S. articles has changed little over the past 10 years, remaining much higher than expected when compared to the overall U.S. share of world articles (figure
U.S. articles are highly cited across all broad scientific fields, with indexes ranging from 1.3 to 2.2. The U.S. indexes across all these fields showed little change between 2002 and 2012. The greatest gain in the index of highly cited articles was in engineering, which grew from 1.7 to 2.0. The indexes for two fields—chemistry and social sciences—declined slightly (appendix table
The EU’s articles are more highly cited than expected in two fields, agriculture (1.2) and physics (1.2) for 2012. The EU’s index values are what would be expected in two fields—astronomy and chemistry.
China is less highly cited than expected in all science fields except computer sciences, chemistry, and geosciences. Impressively, China’s index in computer sciences leaped from 0.2 in 2002 to 1.3 in 2012. Chinese geosciences articles experienced a similar rise from 0.2 to 1.1, while the index for chemistry has now just reached the expected value of 1.0.
Japan’s production of highly cited articles is lower than expected across all fields, although its index increased substantially in astronomy.
The relative citation index (described in the section on “International Citation Patterns”) can also be used to examine the influence that each U.S. sector has on U.S. S&E literature. Figure
Articles authored at federal government institutions always have been cited within the United States more than expected. Although the index value declined almost to 1.0 in the 1990s, it has since risen to 1.09. The U.S. articles with the relative greatest impact are those by nonprofit organizations. Counter to the federal government trend, index values rose over the 1990s to 1.29 but have been in decline in the past 10 years, dropping to 1.14 by 2012.
Citations to the S&E literature on the cover pages of issued patents are one indicator of the contribution of research to the development of inventions. To measure trends consistently, the analysis limits the cited article years to a specific moving window, just as is done for references from articles to articles. Unlike article-to-article citations, however, patents reference much older research, largely due to the length of time that passes from patent application to patent grant (i.e., pendency). Therefore, indicators in this section are based on an 11-year citation window after a 5-year lag. For example, citations from 2012 are references from patents issued in 2012 to articles published from 1997–2007.
According to this indicator, research links to invention increased sharply in the late 1980s and early 1990s (Narin, Hamilton, and Olivastro 1997). At the same time, patenting activity by academic institutions was increasing rapidly, as were patent citations to S&E literature produced across all sectors (NSB 2008:5-49–5-54).
After a slowdown in the late 1990s and early 2000s, referencing from patents to scientific literature is once again increasing. Of utility patents awarded to both U.S. and foreign assignees, 12% cited S&E articles in 2003, and this figure grew to 15% in 2012 (appendix table
Citations to U.S. articles in 2012 USPTO patents were dominated by articles in biological sciences (48%) and medical sciences (23%), along with chemistry (11%), engineering (7%), and physics (7%). These five fields account for 96% of the total (figure
The proportion of U.S. articles cited in U.S. patents that were authored by industry and federal government dropped between 2003 and 2012, largely because citations to academic articles increased (appendix table
Articles from other sectors receive far fewer citations in patents, but this varied by field (figure
Clean energy and energy conservation and related technologies—including biofuels, solar, wind, nuclear, energy efficiency, pollution prevention, smart grid, and carbon sequestration—are closely linked to scientific R&D and have become a policy focus in the United States and other countries. NSF developed a method for identifying patents with potential application in these technologies. (See sidebar “Identifying Clean Energy and Pollution Control Patents” for details on the filters.)
Chapter 6 of this volume presents extensive data on the patents in four technology areas related to clean energy—alternative energy, pollution mitigation, smart grid, and energy storage—including the nationality of their inventors. (See chapter 6, “Industry, Technology, and the Global Marketplace,” section “Patenting of Clean Energy and Pollution Control Technologies.”) This section reports on the citations in those patents to the S&E literature, using those citations to indicate the linkages between S&E R&D and the potential for practical use of the results of those R&D projects in new inventions and technologies. The citation data are based on patents issued between 2003 and 2012.
U.S. patents in these four areas of clean energy technology cite more foreign literature than U.S. literature (appendix table
Within citations to U.S. literature, articles authored by the academic sector accounted for the most citations (70%) among U.S. sectors in 2012. Industry and FRRDCs were the next largest, accounting for 12% and 10% of citations, respectively. Between 2003 and 2012, academia’s share of citations to U.S. literature increased from 59% to 70%. Industry’s share fell from 22% to 12%.
Four broad S&E fields dominate the citations to S&E literature in these four patent areas: chemistry, physics, engineering, and biological sciences. The range of S&E fields cited indicates that these developing technologies rely on a wide base of S&E knowledge.
The S&E fields cited by these patents are shown in table
Using patent citations as an indicator, the data show that chemistry research contributes heavily to invention in all areas of green technology with the exception of smart grid, where engineering dominates. Geoscience articles, which in this taxonomy include environmental sciences, are prominent as well, but only in pollution mitigation.
Academic institutions whose research leads to intellectual property attempt to protect and benefit from the fruits of their labor through patents and associated activities. The majority of U.S. universities did not become actively involved in managing their own intellectual property until late in the 20th century, when the Bayh-Dole Act of 1980 gave colleges and universities a common legal framework for claiming ownership of income streams from patented discoveries that resulted from their federally funded research. Other countries implemented policies similar to the Bayh-Dole Act by the early 2000s, giving their academic institutions (rather than inventors or the government) ownership of patents resulting from government-funded research (Geuna and Rossi 2011). To facilitate the conversion of new knowledge produced in their laboratories to patent-protected public knowledge that potentially can be licensed by others or form the basis for a startup firm, many U.S. research institutions established technology management/transfer offices (AUTM 2009).
The following sections discuss overall trends in university patenting and related indicators through 2011 and 2012.
USPTO granted 8,700 patents to U.S. and foreign universities and colleges in 2012, 3.4% of USPTO patents granted to all U.S. and foreign inventors (figure
Patenting by academic institutions has increased markedly over the last two decades—from 1,800 in 1992 to 8,700 in 2012—resulting in their share of all USPTO patents doubling from 1.8% to 3.4%. Patenting by U.S. institutions outpaced overall growth of USPTO patents in the 1990s, resulting in their share of all patents increasing from 1.6% in 1992 to 2.4% in 1999. Although the number of U.S. academic patents continued to grow from 2000 to 2012, the U.S. university and college share of all USPTO patents declined slightly (appendix table
Patenting by U.S. and foreign universities and colleges in another major patent office, the European Patent Office (EPO), shows a similar trend of increasing activity (figure
The top 200 R&D-performing institutions dominate among U.S. universities and university systems receiving patent protection, with 98% of the total patents granted to U.S. universities between 1997 and 2012 (appendix table
Biotechnology patents accounted for the largest share (25%) of U.S. university patents in 2012 (appendix table
Universities commercialize their intellectual property by granting licenses to commercial firms and supporting start-up firms formed by their faculty. Data from the Association of University Technology Managers (AUTM) indicate continuing growth in a number of such patent-related activities. Invention disclosures filed with university technology management/transfer offices describe prospective inventions and are submitted before a patent application is filed. These grew from 12,600 in 2002 to 19,700 in 2011 (notwithstanding small shifts in the number of institutions responding to the AUTM survey over the same period) (figure
Despite the economic slowdown of the past 5 years, the number of new startup companies formed continued to rise, as did the number of past startups still operating; AUTM survey respondents reported a low of 348 startup companies formed in 2003 and a maximum of 617 in 2011, with a total of extant startup companies in 2011 of 3,573 (appendix table
Most royalties from licensing agreements accrue for relatively few patents and the universities that own them, and many of the AUTM respondent offices report no income. (Thursby and colleagues  report that maximizing royalty income is not the dominant objective of university technology management offices.) At the same time, large one-time payments to a university can affect the overall trend in university licensing income. In 2011, the 157 institutions that responded to the AUTM survey reported a total of $1.5 billion in net royalties from their patent holdings. This is essentially the same amount reported for the last 3 years. Perhaps as a result of the nation’s economic downturn, this number is down sharply from the high value of $2.1 billion reported in 2008 (appendix table