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Tommaso DorigoRSS Feed of this column.

Tommaso Dorigo is an experimental particle physicist, who works for the INFN at the University of Padova, and collaborates with the CMS and the SWGO experiments. He is the president of the Read More »

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"While looking for the decay pi+ ->  e+ nu_e, we focused all our attention on reducing backgrounds, since a prior experiment had set a limit at the level of 10^-6 on the branching ratio. When we heard that an experiment at CERN had seen a signal around 10^-4 I switched from delayed to prompt. The signal was right there, and could have been seen on the first day."

Burton Richter, quoted in  J. Klein, A.Roodman, "Blind Analysis in Nuclear and Particle Physics"

A reader correctly mentions that it is not exactly trivial to understand the above quote without some explanation, so here it is.
Update: I got a confirmation that at the latest INFN board of directors meeting the news was given that the Super-B factory to be built outside Rome is no more. Super-B joins other remarkable projects in high-energy physics -notably the SSC, the American 40-TeV super-collider to be built in Texas, and killed by Congress in 1993- in the dust bin.

With this move the Italian government shows again how little they care for basic research in Italy, and provides further fuel to the escape of bright researchers to other countries.
The top quark is the heaviest of the six known hadron constituents, discovered at the Fermilab Tevatron collider in 1995.  Because of its quite large mass -over forty times more than the second-heaviest bottom quark- and because of a few additional interesting properties, the top quark has stimulated in the past two decades a large amount of theoretical work, well matched to the Tevatron investigations.

In fact, one of the explicit goals of the CDF and DZERO experiments for Run II of the Tevatron, which lasted from 2002 to 2010, was to study extensively the top quark both as a standard model object, subjected as it is to electroweak interactions which can be studied and compared to predictions, and as a portal to new physics of various kinds.
"[...] Given the fact that the nil hypothesis is always false, the rate of Type-I errors is 0%, not 5%, and [...] only Type-II errors can be made, which run typically at about 50% [...] [T]ypically, the sample effect size necessary for significance is notably larger than the actual population effect size and [...] the average of the statistically significant effects is much larger than the actual effect size. The result is that people who do focus on effect sizes end up with a substantial positive bias in their effect size estimation.
UPDATE: BBC radio contacted me to let me know they corrected their mistake. I am very glad to hear that! So you can continue reading BBC after all!

Probability inversion is one of the nastiest mistakes one can do handling the results of a statistical analysis, invalidating to the roots the interpretation of the data to the point that the whole work effectively becomes useless. Unfortunately, it is a very common entertainment for journalists reporting scientific results, and oftentimes scientists themselves fall in the trap.
Maybe more interesting than the just reported result of searches for the Higgs boson into four-lepton final states (ee, eμ, μμ) are the result presented by CMS and ATLAS on the searches for the Higgs decay into tau-lepton pairs. The reason for the interest comes from the fact that last July the rather high rates of Higgs decays to photon pairs had suggested to some that this new particle might have reduced couplings to fermions, and could thus be a non-Standard Model particle after all.