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Astronomical images in the Poisson regime are typically characterized by a spatially varying cosmic background, large variety of source morphologies and intensities, data incompleteness, steep gradients in the data, and few photon counts…

Instrumentation and Methods for Astrophysics · Physics 2012-02-03 Fabrizia Guglielmetti , Rainer Fischer , Volker Dose

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

A commonly used measure to summarize the nature of a photon spectrum is the so-called Hardness Ratio, which compares the number of counts observed in different passbands. The hardness ratio is especially useful to distinguish between and…

Over the past 10 years Bayesian methods have rapidly grown more popular as several computationally intensive statistical algorithms have become feasible with increased computer power. In this paper, we begin with a general description of…

Astrophysics · Physics 2016-02-19 David A. van Dyk , Alanna Connors , Vinay L. Kashyap , Aneta Siemiginowska

We study the problem of non-parametric Bayesian estimation of the intensity function of a Poisson point process. The observations are $n$ independent realisations of a Poisson point process on the interval $[0,T]$. We propose two related…

Methodology · Statistics 2020-03-31 Shota Gugushvili , Frank van der Meulen , Moritz Schauer , Peter Spreij

A Gaussian Cox process is a popular model for point process data, in which the intensity function is a transformation of a Gaussian process. Posterior inference of this intensity function involves an intractable integral (i.e., the…

Methodology · Statistics 2024-07-01 Bingjing Tang , Julia Palacios

The objective Bayesian treatment of a model representing two independent Poisson processes, labelled as "signal" and "background" and both contributing additively to the total number of counted events, is considered. It is shown that the…

Data Analysis, Statistics and Probability · Physics 2015-04-16 Diego Casadei

Searches for faint signals in counting experiments are often encountered in particle physics and astrophysics, as well as in other fields. Many problems can be reduced to the case of a model with independent and Poisson-distributed signal…

Data Analysis, Statistics and Probability · Physics 2017-02-14 Diego Casadei , Cornelius Grunwald , Kevin Kröninger , Florian Mentzel

We present and implement a probabilistic (Bayesian) method for producing catalogs from images of stellar fields. The method is capable of inferring the number of sources N in the image and can also handle the challenges introduced by noise,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Brendon J. Brewer , Daniel Foreman-Mackey , David W. Hogg

In this paper we provide general conditions to check on the model and the prior to derive posterior concentration rates for data-dependent priors (or empirical Bayes approaches). We aim at providing conditions that are close to the…

Statistics Theory · Mathematics 2014-06-18 Sophie Donnet , Vincent Rivoirard , Judith Rousseau , Catia Scricciolo

We present a novel Bayesian framework for inverse problems in which the pos terior distribution is interpreted as the intensity measure of a Poisson point process (PPP). The posterior density is approximated using kernel density estimation,…

Numerical Analysis · Mathematics 2025-10-08 Zhiliang Deng , Zhiyuan Wang , Xiaomei Yang , Xiaofei Guan

Metallicity can be measured by analyzing the spectra in the X-ray region and comparing the flux in spectral lines to the flux in the underlying Bremsstrahlung continuum. In this paper we propose new Bayesian methods which directly model the…

Astrophysics · Physics 2007-05-23 Epaminondas Sourlas , David van Dyk , Vinay Kashyap , Jeremy Drake , Deron Pease

In this paper, two parametric probability distributions capable to describe the statistics of X-ray photon detection by a CCD are presented. They are formulated from simple models that account for the pile-up phenomenon, in which two or…

Instrumentation and Methods for Astrophysics · Physics 2013-10-30 Diego J. R. Sevilla

We present a new method of transient point source deconvolution for coded-aperture X-Ray detectors. Our method is based upon the calculation of the likelihood function and its interpretation as a probability density for the transient source…

Astrophysics · Physics 2008-02-03 Carlo Graziani , Donald Q. Lamb , Raphael Slawinski

A probabilistic technique for the joint estimation of background and sources with the aim of detecting faint and extended celestial objects is described. Bayesian probability theory is applied to gain insight into the coexistence of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 F. Guglielmetti , R. Fischer , V. Dose

The frequentist definition of sensitivity of a search for new phenomena proposed in arXiv:0308063 has been utilized in a number of published experimental searches. In most cases, the simple approximate formula for the common problem of…

Data Analysis, Statistics and Probability · Physics 2020-11-25 Giovanni Punzi

We reconsider a nonparametric density model based on Gaussian processes. By augmenting the model with latent P\'olya--Gamma random variables and a latent marked Poisson process we obtain a new likelihood which is conjugate to the model's…

Machine Learning · Statistics 2018-05-30 Christian Donner , Manfred Opper

In crowd counting datasets, each person is annotated by a point, which is usually the center of the head. And the task is to estimate the total count in a crowd scene. Most of the state-of-the-art methods are based on density map…

Computer Vision and Pattern Recognition · Computer Science 2019-08-13 Zhiheng Ma , Xing Wei , Xiaopeng Hong , Yihong Gong

We present X-sifter, a software package designed for near-optimal detection of sources in X-ray images and other forms of photon images in the Poisson-noise regime. The code is based on the Poisson-noise-matched filter (Ofek & Zackay),…

Instrumentation and Methods for Astrophysics · Physics 2024-12-12 Maayane T. Soumagnac , Eran O. Ofek , Shachar S. Israeli , Guy Nir , Imri A. Dickstein

Given a sample from a discretely observed compound Poisson process, we consider non-parametric estimation of the density $f_0$ of its jump sizes, as well as of its intensity $\lambda_0.$ We take a Bayesian approach to the problem and…

Statistics Theory · Mathematics 2023-02-27 Shota Gugushvili , Frank van der Meulen , Peter Spreij
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