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Testing the homogeneity between two samples of functional data is an important task. While this is feasible for intensely measured functional data, we explain why it is challenging for sparsely measured functional data and show what can be…

Methodology · Statistics 2022-07-05 Changbo Zhu , Jane-Ling Wang

The study of the variation of fundamental constants through time or in localized regions of space is one of the goals of the Cosmic Ray Extremely Distributed Observatory which consists of multiple detectors over the Earth. In this paper,…

High Energy Astrophysical Phenomena · Physics 2022-08-22 D. Alvarez-Castillo

Experimentation platforms in industry must often deal with customer trust issues. Platforms must prove the validity of their claims as well as catch issues that arise. As a central quantity estimated by experimentation platforms, the…

Methodology · Statistics 2025-11-21 Kedar Karhadkar , Jack Klys , Daniel Ting , Artem Vorozhtsov , Houssam Nassif

Real-world data typically contain a large number of features that are often heterogeneous in nature, relevance, and also units of measure. When assessing the similarity between data points, one can build various distance measures using…

Machine Learning · Statistics 2022-05-27 Aldo Glielmo , Claudio Zeni , Bingqing Cheng , Gabor Csanyi , Alessandro Laio

Astrophysical tests of the stability of fundamental couplings are becoming an increasingly important probe of new physics. Motivated by the recent availability of new and stronger constraints we update previous works testing the consistency…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-31 C. J. A. P. Martins , A. M. M. Pinho

Three aspects of time series are uncertainty (dispersion at a given time scale), scaling (time-scale dependence), and intermittency (inclination to change dynamics). Simple measures of dispersion are the mean absolute deviation and the…

Probability · Mathematics 2007-05-23 David R. Bickel

We test against two different sets of data an apparently new approach to the analysis of the variance of a numerical variable which depends on qualitative characters. We suggest that this approach be used to complement other existing…

The observational evidence for the recent acceleration of the universe demonstrates that canonical theories of cosmology and particle physics are incomplete---if not incorrect---and that new physics is out there, waiting to be discovered. A…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-12 C. J. A. P. Martins

We set up a framework for a model-independent analysis of the time variation of $e$, $\hbar$, and $c$ indiviually. It is shown that the time-evolution of each constant can be determined uniquely from the time evolution of the fine structure…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. Yu. Ignatiev , B. J. Carson

The Allan variance is a standard technique to characterise the stability of spectroscopic instruments used in astronomical observations. The period for switching between source and reference measurement is often derived from the Allan…

Astrophysics · Physics 2009-11-13 Volker Ossenkopf

Many modern theories predict that the fundamental constants depend on time, position, or the local density of matter. We develop a spectroscopic method for pulsed beams of cold molecules, and use it to measure the frequencies of microwave…

We investigate the triple-alpha process and the Oklo phenomenon to obtain constraints on possible cosmological time variations of fundamental constants. Specifically we study cosmological temporal constraints for the fine structure constant…

Astrophysics · Physics 2009-11-07 H. Oberhummer , A. Csoto , M. Fairbairn , H. Schlattl , M. M. Sharma

Calculation of the Dirac hydrogen atom spectrum in the framework of dynamical fine structure constant (alpha) variability discloses a small departure in the laboratory from Sommerfeld's formula for the fine structure shifts, possibly…

Astrophysics · Physics 2007-05-23 Jacob D. Bekenstein

Discussion of the constancy, or otherwise, of the various so-called universal constants which abound in physics has continued for many years. However, relatively recent observations, which appear to indicate a variation in the value of the…

General Physics · Physics 2007-08-21 A. D. Law , J. Dunning-Davies

That the laws of physics are the same at all times and places throughout the Universe is one of the basic assumptions of physics. Astronomical observations provide the only means to test this basic assumption on cosmological time and…

Instrumentation and Methods for Astrophysics · Physics 2019-04-10 Xi Chen , Simon P. Ellingsen , Ying Mei

To understand their data better, astronomers need to use statistical tools that are more advanced than traditional ``freshman lab'' statistics. As an illustration, the problem of combining apparently incompatible measurements of a quantity…

Astrophysics · Physics 2007-05-23 William H. Press

Uncertainty quantification is a key part of astronomy and physics; scientific researchers attempt to model both statistical and systematic uncertainties in their data as best as possible, often using a Bayesian framework. Decisions might…

Instrumentation and Methods for Astrophysics · Physics 2022-07-29 Peter Hatfield

We propose a new asymptotic test to assess the stationarity of a time series' mean that is applicable in the presence of both heteroscedasticity and short-range dependence. Our test statistic is composed of Gini's mean difference of local…

Statistics Theory · Mathematics 2021-08-23 Sara Kristin Schmidt

Quantifying uncertainty in detected changepoints is an important problem. However it is challenging as the naive approach would use the data twice, first to detect the changes, and then to test them. This will bias the test, and can lead to…

Methodology · Statistics 2026-05-11 Rachel Carrington , Paul Fearnhead

Binary classification is a fundamental task in machine learning, with applications spanning various scientific domains. Whether scientists are conducting fundamental research or refining practical applications, they typically assess and…

Machine Learning · Computer Science 2023-10-20 Attila Fazekas , György Kovács
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