UPDATE: for more on this, I only now realize that my friend at Resonaances had written about it yesterday... It is nice to see that he agrees with my conclusions, anyway. Also Peter has news on it, and as usual additional links...

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My ATLAS colleagues will have to pardon me for the slightly sensationalistic title of this article, but indeed the question is one which many inside and outside CERN are asking themselves upon looking into the new public material of ATLAS Higgs boson searches using the 2011 dataset in conjunction with the first part of 2012 data.

This is a post about basics. That's because I think a point needs to be made which is surprisingly not as well-known as its elementary nature would have you guess.

Correlation -in its most used version, due to Pearson- is a measure of how two quantities can be observed to be in linear dependence on one another. It is a very common quantity to report the results of scientific studies, particularly but not exclusively in the social sciences. Researchers try to evidence the presence of a correlation between two phenomena as a preliminary step to investigating whether one can be the cause of the other.

In High-Energy Physics the small p-value of an observation may be the first hint of a discovery about to be made. Here by p-value I just mean the probability, just to be fancy (or brief). Because we rely on the assessment of the rarity of observations to decide whether we have discovered something or not, we physicists are (or should be) really careful with p-values. Today's article aims at demonstrating how easy it is to be carried away into giving more relevance to an observation than we should.

A new preprint is out in the arxiv today, detailing the results of a new analysis of neutrino speeds performed by the OPERA collaboration using proton spills of the CNGS beam produced during dedicated runs in May this year.