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Related papers: Biased Moments of Undersampled Sources

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In high-energy astrophysics, it is common practice to account for the background overlaid with the counts from the source of interest with the help of auxiliary measurements carried on by pointing off-source. In this "on/off" measurement,…

Instrumentation and Methods for Astrophysics · Physics 2014-12-12 Diego Casadei

Event cameras output asynchronous events to represent intensity changes with a high temporal resolution, even under extreme lighting conditions. Currently, most of the existing works use a single contrast threshold to estimate the intensity…

Computer Vision and Pattern Recognition · Computer Science 2020-12-18 Ziwei Wang , Yonhon Ng , Pieter van Goor , Robert Mahony

Stacking analysis is a means of detecting faint sources using a priori position information to estimate an aggregate signal from individually undetected objects. Confusion severely limits the effectiveness of stacking in deep surveys with…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Peter Kurczynski , Eric Gawiser

In a focused ion beam (FIB) microscope, source particles interact with a small volume of a sample to generate secondary electrons that are detected, pixel by pixel, to produce a micrograph. Randomness of the number of incident particles…

Medical Physics · Physics 2023-08-15 Minxu Peng , John Murray-Bruce , Vivek K Goyal

The magnification effects of clustered matter produce variations in the image sizes and number density of galaxies across the sky. This paper advocates the use of these effects in wide field surveys to map large-scale structure and the…

Astrophysics · Physics 2009-11-07 Bhuvnesh Jain

Astronomers are often confronted with funky populations and distributions of objects: brighter objects are more likely to be detected; targets are selected based on colour cuts; imperfect classification yields impure samples. Failing to…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-21 Samuel R. Hinton , Alex Kim , Tamara M. Davis

In addition to the intrinsic clustering of galaxies themselves, the spatial distribution of galaxies observed in surveys is modulated by the presence of weak lensing due to matter in the foreground. This effect, known as magnification bias,…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-09 Lukas Wenzl , Shi-Fan Chen , Rachel Bean

We aim to present a tutorial on the detection, parameter estimation and statistical analysis of compact sources (far galaxies, galaxy clusters and Galactic dense emission regions) in cosmic microwave background observations. The topic is of…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-05 D. Herranz , P. Vielva

Camouflage is primarily context-dependent yet current metrics for camouflaged scenarios overlook this critical factor. Instead, these metrics are originally designed for evaluating general or salient objects, with an inherent assumption of…

Computer Vision and Pattern Recognition · Computer Science 2026-01-27 Chen-Yang Wang , Gepeng Ji , Song Shao , Ming-Ming Cheng , Deng-Ping Fan

We develop a Bayesian framework for sensing which adapts the sensing time and/or basis functions to the instantaneous sensing quality measured in terms of the expected posterior mean-squared error. For sparse Gaussian sources a significant…

Information Theory · Computer Science 2018-02-12 Ralf R. Müller , Ali Bereyhi , Christoph F. Mecklenbräuker

In experiment, the multiplicity distributions of inelastic processes are truncated due to finite energy, insufficient statistics or special choice of events. It is shown that the moments of such truncated multiplicity distributions possess…

High Energy Physics - Phenomenology · Physics 2015-06-25 I. M. Dremin , V. A. Nechitailo

This paper gives a review of concentration inequalities which are widely employed in non-asymptotical analyses of mathematical statistics in a wide range of settings, from distribution-free to distribution-dependent, from sub-Gaussian to…

Statistics Theory · Mathematics 2025-02-24 Huiming Zhang , Song Xi Chen

We examine the errors on counts in cells extracted from galaxy surveys. The measurement error, related to the finite number of sampling cells, is disentangled from the ``cosmic error'', due to the finiteness of the survey. Using the…

Astrophysics · Physics 2009-10-28 István Szapudi , Stéphane Colombi

The bispectrum is the lowest-order statistic sensitive to the shape of structures generated by gravitational instability and is a potentially powerful probe of galaxy biasing and the Gaussianity of primordial fluctuations. Although the…

Astrophysics · Physics 2009-10-31 Roman Scoccimarro

Gravitational microlensing surveys target very dense stellar fields in the local group. As a consequence the microlensed source stars are often blended with nearby unresolved stars. The presence of `blending' is a cause of major uncertainty…

Astrophysics · Physics 2009-11-13 Martin C. Smith , Przemyslaw Wozniak , Shude Mao , Takahiro Sumi

Context. Weak lensing and clustering statistics beyond two-point functions can capture non-Gaussian information about the matter density field, thereby improving the constraints on cosmological parameters relative to the mainstream methods…

The space-time correlations of streams of photons can provide fundamentally new channels of information about the Universe. Today's astronomical observations essentially measure certain amplitude coherence functions produced by a source.…

Instrumentation and Methods for Astrophysics · Physics 2009-03-03 C. Barbieri , M. K. Daniel , W. J. de Wit , D. Dravins , H. Jensen , P. Kervella , S. Le Bohec , F. Malbet , P. Nunez , J. P. Ralston , E. N. Ribak

Most optical and IR spectra are now acquired using detectors with finite-width pixels in a square array. This paper examines the effects of such pixellation, using computed simulations to illustrate the effects which most concern the…

Instrumentation and Methods for Astrophysics · Physics 2017-09-05 J. Gordon Robertson

In machine learning models, the estimation of errors is often complex due to distribution bias, particularly in spatial data such as those found in environmental studies. We introduce an approach based on the ideas of importance sampling to…

Machine Learning · Computer Science 2023-09-15 Boris Prokhorov , Diana Koldasbayeva , Alexey Zaytsev

When light is passed through aberrated optical systems, the resulting degradation in amplitude and phase has deleterious effects, for example, on resolution in imaging, spot sizes in focussing, and the beam quality factor of the output…

Optics · Physics 2022-01-19 Wagner Tavares Buono , Jacuqueline Tau , Isaac Nape , Andrew Forbes