Two interesting papers from NBER.
Research which explores unchartered waters has a high potential for major impact but also carries a higher uncertainty of having impact. Such explorative research is often described as taking a novel approach. This study examines the complex relationship between pursuing a novel approach and impact. Viewing scientific research as a combinatorial process, we measure novelty in science by examining whether a published paper makes first time ever combinations of referenced journals, taking into account the difficulty of making such combinations. We apply this newly developed measure of novelty to all Web of Science research articles published in 2001 across all scientific disciplines. We find that highly novel papers, defined to be those that make more (distant) new combinations, deliver high gains to science: they are more likely to be a top 1% highly cited paper in the long run, to inspire follow on highly cited research, and to be cited in a broader set of disciplines. At the same time, novel research is also more risky, reflected by a higher variance in its citation performance. In addition, we find that novel research is significantly more highly cited in “foreign” fields but not in its “home” field. We also find strong evidence of delayed recognition of novel papers and that novel papers are less likely to be top cited when using a short time window. Finally, novel papers typically are published in journals with a lower than expected Impact Factor. These findings suggest that science policy, in particular funding decisions which rely on traditional bibliometric indicators based on short-term direct citation counts and Journal Impact Factors, may be biased against “high risk/high gain” novel research. The findings also caution against a mono-disciplinary approach in peer review to assess the true value of novel research.
We study the extent to which eminent scientists shape the vitality of their areas of scientific inquiry by examining entry rates into the subfields of 452 academic life scientists who pass away prematurely. Consistent with previous research, the flow of articles by collaborators into affected fields decreases precipitously after the death of a star scientist. In contrast, we find that the flow of articles by non-collaborators increases by 8.6% on average. These additional contributions are disproportionately likely to be highly cited. They are also more likely to be authored by scientists who were not previously active in the deceased superstar's field. Intellectual, social, and resource barriers all impede entry, with outsiders only entering subfields that offer a less hostile landscape for the support and acceptance of “foreign” ideas. Overall, our results suggest that once in control of the commanding heights of their fields, star scientists tend to hold on to their exalted position a bit too long.