Science and Engineering Indicators 2012

U.S. Survey Data Sources

International Survey Data Sources

The Blending of Print and Online Sources of Science News

Internet news sites sometimes represent new providers of news and other times represent an alternative outlet for reporting done by print or broadcast media organizations. The 2010 General Social Survey asked half the sample a question with response options that distinguish between online and print-format sources for newspapers and magazines.

Print media organizations are more likely to serve as a primary source of Americans' information about current news events than they are about either S&T or specific scientific issues. When it comes to news about current events, a roughly equal proportion of Americans who primarily rely on the Internet do so via online venues of print media organizations and other online sources (12% and 11% of adults, respectively). Print media organizations are less dominant as sources of news about general S&T. Eleven percent of Americans rely on Internet sources for S&T news provided by print media organizations; nearly twice as many use other online sources (20%). A majority of Americans seeking information about specific scientific issues say the Internet would be their primary source, 12% would rely on online information from print media organizations, and 48% would rely on other online sources.

Measuring Factual Science Knowledge Over Time

How to measure factual knowledge about science over time is a difficult puzzle, in part because the generally accepted principles and facts of scientific fields are constantly in flux. The items in the factual knowledge index were first developed in the 1970s and aimed to tap a selection of science facts that would likely withstand the "test of time" (Miller 1998, 2011). The index aims to measure the extent to which the public has a clear understanding of the factual aspects of major scientific fields in the biological and physical sciences. The proportion of the public that provides the correct answer on any one question is less important than the pattern of responses across the set of questions used in the factual knowledge index.

As science changes and public knowledge about science changes, the exact questions that best distinguish individuals who tend to know more about science from those who tend to know less are likely to vary over time. As a result, periodic review of indicators such as these is warranted. A number of studies and analyses have been commissioned by NSF for this purpose over the years. NSF is in the process of undertaking further review and experimentation with the factual knowledge questions.

Two items used in past versions of the index have received considerable scrutiny; one concerned the "big bang" and the other concerned evolution. In the 2010 GSS, 45% of Americans answered "true" that "the universe began with a huge explosion." There was some concern that the wording of this question erred too heavily on the side of using easily comprehensible language at the cost of scientific precision. This may prompt some highly knowledgeable respondents to think that the item blurs or neglects important distinctions, and in a few cases may lead respondents to answer the question incorrectly. The other item of some concern was "human beings, as we know them today, developed from earlier species of animals." In the 2010 GSS, half of Americans answered "true" to the question about evolution. As discussed elsewhere in the chapter, evidence from a 2004 survey-based experiment suggests that responses to these items reflect more than familiarity with the concepts. (Also see NSB 2008.)

As measures of science knowledge, these questions correlate with the overall index, but the correlations for other items are generally stronger. A statistical review conducted by the Research Triangle Institute on behalf of NSF in 2004 found that all the knowledge questions, including the evolution and "big bang" questions, reflect a single underlying dimension of factual knowledge (Bann and Schwerin 2004). Later analyses have replicated this finding over time. Thus, the social science foundation for using either 11 items or 9 items together in one scale is well-supported.

This chapter relies on the 9-item factual knowledge scale for analysis of trends in knowledge over time. Responses to the 9-item factual knowledge scale and an 11-item factual knowledge scale that includes responses to the questions on evolution and the "big bang" are highly correlated with each other. Whether or not these two questions are included in a scale of factual science knowledge has little bearing on the summary portrait of Americans' knowledge that the scale conveys. In addition, knowledge differences between population groups (e.g., men and women) are similar (appendix table 7-10). Table 7-B shows that, on average, respondents in the top quartile on the trend factual knowledge scale answered 87% of the questions on the 11-item version of the scale correctly and 59% of the two additional items correctly. Those in the lower quartiles on the trend factual knowledge scale answered fewer items correctly.

Public Understanding of Science and Its Role in Everyday Life

Indicators of public understanding about S&T can serve many purposes. NSF held two workshops in fall 2010 with social science experts from multiple disciplines and backgrounds to review how best to conceptualize and measure public understanding of science and engineering (Guterbock et al. 2010; Toumey et al. 2010). The workshop participants endorsed the past measures reported by NSF as useful indicators of public understanding and suggested approaches for developing additional or improved indicators. The workshop participants also endorsed the need to monitor and evaluate all indicators on an ongoing basis so that adjustments to the indicators can be implemented when needed.

The NSF-sponsored workshops identified three key functions of public knowledge about S&T. First, knowledge facilitates civic engagement with science, particularly when technologies raise emerging issues that intersect science and society. Examples of these kinds of situations include public debates at the local, state, or national levels about nuclear power and nuclear waste disposal, and debates about the role and funding of embryonic stem cell research. Second, knowledge facilitates decisionmaking in everyday life, particularly when S&T intersects with citizens' work, home, and leisure activities. Some examples include knowledge about antibiotic medications and their appropriate usage, and the principles of heat and electricity as they relate to home use. A third function of science knowledge is broadly framed as knowledge for the sake of knowing more about the world and how it works, addressing human curiosity in ways that go beyond instrumental needs for practical knowledge. This three-part framework for the role and function of public knowledge about S&T helps inform the standards against which one can judge the kinds of knowledge that are important for citizens to hold and whether the public knows "enough" about science for these three purposes.

Three different types of knowledge were identified: factual science knowledge, knowledge of scientific processes and standards for evaluating scientific evidence, and knowledge about the institutions that play a role in scientific development and how those institutions operate (also see Shen 1975). NSF surveys have included measures of both factual science knowledge and understanding of scientific processes for a number of years. Indicators of how well the public understands the workings of institutions engaged in S&T development have not been included in past NSF surveys. Research by Bauer, Petkova, and Boyadjieva (2000) developed one set of measures along these lines in surveys of the British and Bulgarian publics.

Apart from evaluating the purposes and function of the NSF indicators of public knowledge, the workshops also raised additional questions for social scientists to explore, such as research on the kinds of things that motivate greater learning about S&T and a better understanding of how such adult learning occurs.

Differences Between Scientists and the Public on S&T-related Issues

Directly comparable data on the degree to which public attitudes align with those of scientists is scarce. A study conducted by the Pew Research Center in 2009 asked the same questions of a sample of scientists belonging to the AAAS and a representative sample of the general public. The study found a striking difference between the groups across a number of specific issues including climate change, nuclear power, embryonic stem cell research, evolution, and animal research.

The public tends to underestimate the degree of consensus among scientists about evolution. Six in ten said that scientists generally agree that humans have evolved over time, and 28% said they do not generally agree about this. The survey of scientists found that 97% of scientists say that humans and other living things have evolved over time.

The public also tends to underestimate the degree of consensus among scientists about climate change; 56% said that scientists generally agree that the earth is getting warmer because of human activity, and 35% said scientists do not generally agree about this. The survey of scientists found 84% of scientists say that "the earth is getting warmer mostly because of human activity such as burning fossil fuels." A survey of earth scientists by Doran and Zimmerman (2009) also found strong consensus among scientists that the earth's temperature is rising and that human activity is "a significant contributing factor in changing mean global temperatures."