Tag Archives: nobel laureates

The wrong impact

“We just got a paper in an Impact Factor 10 journal … and hope to go higher soon.”  That’s a statement made to me last week.  It is wrong on so many levels, but does it matter?   Nobel Prize winners think so. This video from nobelprize.org appeared in my twitter feed on Friday.  Before you watch it, consider this, academics in NZ are being encouraged in promotion applications and in preparing for the next round of NZ Performance Based Research Fund (PBRF), which will allocate millions of dollars to academic institutions, to include a metric of the ranking of the journal.  The Impact Factor is the most common metric available.


ps. I would not allow a student working with me to present a raw mean of a highly skewed distribution because it so very poorly represents the distribution.  However, this is exactly what the Impact Factor does (for those who don’t know the most common impact factor for a journal in any given year is simply the sum of citations of articles from the preceding two years divided by the total number of articles published.  The citation distribution is usually skewed because the vast majority of articles receive very few citations in such a short time, but a few receive a lot).  There are numerous other problems with it, not the least that it can’t be used to compare “impact” between different disciplines.

Note to self – eat more chocolate

Apparently the pinnacle of one’s scientific career is to win a Nobel Prize.  Having not won a Nobel yet I will just need to accept by faith that it would indeed be the pinnacle of my career.  Thanks to a brilliant article in the New England Journal of Medicine this week I now have a new strategy to gain that elusive medal – eat more chocolate.  Dr Franz Messerli has nicely illustrated that the number of Nobel laureates per 10 million of population is correlated well with the chocolate consumption of the country of origin of the laureates (Messerli FH. Chocolate Consumption, Cognitive Function, and Nobel Laureates. N Engl J Med 2012;).  The correlation is strong with an r=0.79* (p<0.0001**) increasing to 0.86 with the removal of one outlier (Sweden). As the author wrote:

“..since chocolate consumption has been documented to improve cognitive function, it seems most likely that in a dose-dependent way, chocolate intake provides the abundant fertile ground needed for the sprouting of Nobel laureates. Obviously, these findings are hypothesis-generating only and will have to be tested in a prospective, randomized trial.”

On the outlier he wrote:

“The only possible outlier seems to be Sweden. Given its per capita chocolate consumption of 6.4 kg per year, we would predict that Sweden should have produced a total of about 14 Nobel laureates, yet we observe 32. Considering that in this instance the observed number exceeds the expected number by a factor of more than 2, one cannot quite escape the notion that either the Nobel Committee in Stockholm has some inherent patriotic bias when assessing the candidates for these awards or, perhaps, that the Swedes are particularly sensitive to chocolate, and even minuscule amounts greatly enhance their cognition.”

You may wonder why this was not published on 1 April .  Is this merely another example of “correlation doesn’t equal causation” and the tyranny of the p value (more on that in another post), or could there really be something in it? Have a read of the article and judge for yourself.

No good scientific report is worth its salt without a testimonial (here):

“I attribute essentially all my success to the very large amount of chocolate that I consume,” said Eric Cornell, an American physicist who shared the Nobel Prize in 2001.

“Personally I feel that milk chocolate makes you stupid,” he added. “Now dark chocolate is the way to go. It’s one thing if you want like a medicine or chemistry Nobel Prize, OK, but if you want a physics Nobel Prize it pretty much has got to be dark chocolate.”

*  if r=1 then correlation is perfect, if r=0 then there is nor correlation at all.  0.79 is impressive.

** this means that there is a .01% chance that the correlation observed was due to random chance.