![]() I wanted to show this plot because, when some texts show confidence interval simulations like this they use the same distribution for each trial. The interval covered the true value 94.33 % of the time. I did this 10,000 times (only 50 are shown). The blue interval shows the one time that the confidence interval did not trap the median. I did this many times, each time using a different distribution with a different true median. Then I generated the data and constructed the interval. In the first simulation I picked some distribution. Quoting: "The plot shows the first 50 simulations. ![]() (The author is a stats professor at CMU.) You don't need identical replications of the same experiment, just long run probabilities for any application of the method. ![]() And the standard model is extremely successful and well confirmed. I know these people are incredibly smart and conscientious. In the end it turned out to be caused by the deformation of the ATLAS detector by its own weight of more than 7000 tons over time. Indeed he was right - we have not been considering this effect in our simulations, however - after some calculations and speaking to the machine experts - it turned out that this effect induces a feature in our data, which is opposite in sign that we observe so we have been left with an effect that was twice as large and unexplained. Once one of my PhD students came into my office and told that he finally figured out this feature: the protons in the ATLAS detector do not collide heads-on but under a very small angle, allowing the not interacting protons to continue their travel through the LHC on the other side of the experiment. > We observed for quite some time some features in the our data, which we could not explain. Cranmer who is one of the folks who developed the standard statistical formalism and methods used in modern particle physics experiments. that certain nuisance parameters are "nicely" distributed and uncorrelated. Unless the combination is specifically taking into account correlations between uncertainties at the different experiments on the same collider (which exist, but it's really hard to handle).Īnother take many people in the field are expressing is that it's simply infeasible to reliably interpret statistical models at that level (especially one that is dominated by systematic uncertainty), since they are based on approximations and assumptions e.g. I'm not sure I agree so much with the point of combining the LEP experiments, which do have some tension with each other. He is very politely arguing that "someone messed up". As another ATLAS physicist, I can say that this is an excellent article from Prof.
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