arXiv subjects

M. Laveder

Publications and source records attributed to M. Laveder.

40 records · Page 3Linked to original sources

arXiv2001

The Physical Significance of Confidence Intervals

We define some appropriate statistical quantities that indicate the physical significance (reliability) of confidence intervals in the framework of both Frequentist and Bayesian statistical theories. We consider the expectation value of the upper limit in the absence of a signal (that we propose to call "exclusion potential", instead of "sensitivity" as done by Feldman and Cousins) and its standard deviation, we define the "Pull" of a null result, expressing the reliability of an experimental upper limit, and the "upper and lower detection functions", that give information on the possible outcome of an experiment if there is a signal. We also give a new appropriate definition of "sensitivity", that quantifies the capability of an experiment to reveal the signal that is searched for at the given confidence level.

hep-ex↗

arXiv2000

The Power of Confidence Intervals

We consider the power to reject false values of the parameter in Frequentist methods for the calculation of confidence intervals. We connect the power with the physical significance (reliability) of confidence intervals for a parameter bounded to be non-negative. We show that the confidence intervals (upper limits) obtained with a (biased) method that near the boundary has large power in testing the parameter against larger alternatives and small power in testing the parameter against smaller alternatives are physically more significant. Considering the recently proposed methods with correct coverage, we show that the physical significance of upper limits is smallest in the Unified Approach and highest in the Maximum Likelihood Estimator method. We illustrate our arguments in the specific cases of a bounded Gaussian distribution and a Poisson distribution with known background.

hep-ex↗

arXiv2000

The flavor of neutrinos in muon decays at a neutrino factory and the LSND puzzle

The accurate prediction of the neutrino beam produced in muon decays and the absence of opposite helicity contamination for a particular neutrino flavor make a future neutrino factory the ideal place to look for the lepton flavor violating (LFV) decays of the kind $μ^+\ra e^+\nuebar\numu$ and lepton number violating (LNV) processes like $μ^-\ra e^-\nue\numu$. Excellent sensitivities can be achieved using a detector capable of muon and/or electron identification with charge discrimination. This would allow to set experimental limits that improve current ones by more than two orders of magnitude and test the hypothesis that the LSND excess is due to such anomalous decays, rather than neutrino flavor oscillations in vacuum.

hep-ph↗

arXiv2000

Large nu_mu->nu_tau and nu_e->nu_tau transitions in short-baseline experiments?

Considering four-neutrino schemes of type 3+1, we identify four small regions of the neutrino mixing parameter space compatible with all data. Assuming a small mixing between the sterile neutrino and the isolated mass eigenstate we show that large nu_mu->nu_tau and nu_e->nu_tau transitions are predicted in short-baseline experiments and could be observed in the near future in dedicated experiments. We discuss also implications for solar, atmospheric and long-baseline neutrino experiments and we present a formalism that allows to describe in 3+1 schemes atmospheric neutrino oscillations, long-baseline nu_mu disappearance and nu_mu->nu_tau transitions in matter.

hep-ph↗