Key Papers of the 2010 Nobel Laureates

The list above - of papers specifically cited by the committees of the 2010 Nobel prizes in physiology or medicine, physics, chemistry and economics when making their awards - invites several observations related to research influence and citations.

The prize to Robert G. Edwards for the development of in vitro fertilisation was based on a series of publications from 1965 to 1978. The most cited of these is the 1978 letter to The Lancet, which relates the facts surrounding the birth of Louise Joy Brown. It is not a detailed research report and contains no references. The nature of the breakthrough in IVF was conceptual and procedural; it was also controversial. These facts together would seem to offer some explanation for the relatively modest number of citations to these key papers.

In this case, citation counts fail to adequately represent the impact on research of the achievement of Professor Edwards and the late P.C. Steptoe, to say nothing of its enormous importance for infertile couples and society at large.

The physics prize provides a contrast in several ways. The winners' 2004 paper in Science has already been cited more than 3,200 times - and in only six years. This record makes it the second most cited original research report in physics in the past decade.

For this reason, Thomson Reuters predicted in 2008 that Andre Geim and Konstantin Novoselov would receive a Nobel prize for the discovery of graphene. The surprise, perhaps, was the swiftness with which the prize was awarded. A two-decade lag between discovery and the announcement of a Nobel prize is typical, although there have been a few prizes recently that have been awarded within a decade of discovery. The timing of the physics prize is at the other end of the spectrum compared with the prize in physiology or medicine, which came 32 years after the birth of Louise Brown.

The citation record of the winners of the chemistry prize, for closely related work on palladium-catalysed cross-coupling reactions, has been widely expected by the chemistry community for years. The committee acknowledged "many players" in the field, but by necessity (the rules of Alfred Nobel's will limiting a prize to three persons at most) identified the pioneers in its judgement.

The utility of the Heck, Negishi and Suzuki reactions would seem to be far greater than represented by the citation counts to the key papers listed here. The 1972 paper by Robert Heck and J.P. Nolley, the most cited of the group, does not even rank in the top 200 of research reports in chemistry published in the 1970s. Why? The likely explanation, at least in the context of academic research, is obliteration by incorporation, which describes those cases in which a finding is so well known that explicit citation is no longer required. The late Joshua Lederberg, winner of the Nobel Prize in Physiology or Medicine in 1958, once remarked: "The work that everybody knows...is hardly cited at all!"

It is interesting to note, however, that citations to these key papers have risen somewhat in the past decade or two, as the Heck, Negishi and Suzuki reactions have been increasingly applied in the pharmaceutical, agricultural and materials industries. And this may indicate another citation phenomenon - delayed recognition - at least from the standpoint of industry.

The Nobel Prize in Economics recognised the work of three researchers for their analyses of markets with search and matching frictions. Their work has appeared in a great many papers published from 1970 onwards. Seven of their most influential papers are listed above. Of these, the most cited are Peter Diamond's 1982 paper in the Journal of Political Economy and the 1994 article by Dale Mortensen and Christopher Pissarides in the Review of Economic Studies. Again, there are many papers in economics journals that have been more heavily cited over this long period. In this case, it would seem, their work was spread out across a series of successive reports that built upon each other, and for that reason the citation record is also dispersed widely.

Next week: national ranking in neuroscience and behaviour.