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A new method for improving the resolution of astronomical images is presented. It is based on the principle that sampled data cannot be fully deconvolved without violating the sampling theorem. Thus, the sampled image should not be…

Astrophysics · Physics 2009-10-30 P. Magain , F. Courbin , S. Sohy

Ongoing and future spectroscopic surveys will measure numerous galaxy redshifts within tens of thousands of galaxy clusters. However, the sampling within these clusters will be low, 15 < N < 50 per cluster. With such data, it will be…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-18 Daniel Gifford , Nicholas Kern , Christopher J. Miller

Consider a Gaussian memoryless multiple source with $m$ components with joint probability distribution known only to lie in a given class of distributions. A subset of $k \leq m$ components are sampled and compressed with the objective of…

Information Theory · Computer Science 2018-03-16 Vinay Praneeth Boda

Multi-wavelength astronomical studies brings a wealth of science within reach. One way to achieve a cross-wavelength analysis is via `stacking', i.e. combining precise positional information from an image at one wavelength with data from…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-14 Song Chen , Jonathan T. L. Zwart , Mario G. Santos

We show how to obtain a Bayesian estimate of the rates or numbers of signal and background events from a set of events when the shapes of the signal and background distributions are known, can be estimated, or approximated; our method works…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Will M. Farr , Jonathan R. Gair , Ilya Mandel , Curt Cutler

Spaces of convex and concave functions appear naturally in theory and applications. For example, convex regression and log-concave density estimation are important topics in nonparametric statistics. In stochastic portfolio theory, concave…

Probability · Mathematics 2021-05-25 Peter Baxendale , Ting-Kam Leonard Wong

This paper analyses the effect of preferential sampling in Geostatistics when the choice of new sampling locations is the main interest of the researcher. A Bayesian criterion based on maximizing utility functions is used. Simulated studies…

Statistics Theory · Mathematics 2015-09-23 Gustavo da Silva Ferreira , Dani Gamerman

Two commonly arising computational tasks in Bayesian learning are Optimization (Maximum A Posteriori estimation) and Sampling (from the posterior distribution). In the convex case these two problems are efficiently reducible to each other.…

Machine Learning · Computer Science 2019-11-07 Kunal Talwar

Counting galaxy number density with wide range sky surveys has been well adopted in researches focusing on revealing evolution pattern of different types of galaxies. As understood intuitively the astrophysics environment physics is…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-26 K. J. Shen , Q. Zhang , Xin-he Meng

The number density of galaxy clusters across mass and redshift has been established as a powerful cosmological probe. Cosmological analyses with galaxy clusters traditionally employ scaling relations. However, many challenges arise from…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-08 M. Kosiba , N. Cerardi , M. Pierre , F. Lanusse , C. Garrel , N. Werner , M. Shalak

For galaxy clustering to provide robust constraints on cosmological parameters and galaxy formation models, it is essential to make reliable estimates of the errors on clustering measurements. We present a new technique, based on a spatial…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Peder Norberg , Enrique Gaztanaga , Carlton M. Baugh , Darren J. Croton

The incredible variety of galaxy shapes cannot be summarized by human defined discrete classes of shapes without causing a possibly large loss of information. Dictionary learning and sparse coding allow us to reduce the high dimensional…

Astrophysics of Galaxies · Physics 2014-07-01 Giuseppe Vinci , Peter Freeman , Jeffrey Newman , Larry Wasserman , Christopher Genovese

We consider Bayesian linear regression with sparsity-inducing prior and design efficient sampling algorithms leveraging posterior contraction properties. A quasi-likelihood with Gaussian spike-and-slab (that is favorable both statistically…

Computation · Statistics 2023-07-13 Qijia Jiang

In certain situations that shall be undoubtedly more and more common in the Big Data era, the datasets available are so massive that computing statistics over the full sample is hardly feasible, if not unfeasible. A natural approach in this…

Machine Learning · Statistics 2015-01-12 Stéphan Clémençon , Patrice Bertail , Emilie Chautru , Guillaume Papa

The Shannon entropy, and related quantities such as mutual information, can be used to quantify uncertainty and relevance. However, in practice, it can be difficult to compute these quantities for arbitrary probability distributions,…

Computation · Statistics 2017-10-11 Brendon J. Brewer

In particle-in-cell simulations and some other statistical computations, the representation of modelled distributions with tracked macro-particles can become locally excessive. Merging or resampling dense clusters or highly-populated phase…

Computational Physics · Physics 2020-12-21 Arkady Gonoskov

With the advent of galaxy surveys which provide large samples of galaxies or galaxy clusters over a volume comparable to the horizon size (SDSS-III, HETDEX, Euclid, JDEM, LSST, Pan-STARRS, CIP etc.) or mass-selected large cluster samples…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Licia Verde

It is well known that the clustering of galaxies depends on galaxy type.Such relative bias complicates the inference of cosmological parameters from galaxy redshift surveys, and is a challenge to theories of galaxy formation and evolution.…

We theoretically study semi-supervised clustering in sparse graphs in the presence of pairwise constraints on the cluster assignments of nodes. We focus on bi-cluster graphs, and study the impact of semi-supervision for varying constraint…

Data Analysis, Statistics and Probability · Physics 2011-11-01 Greg Ver Steeg , Aram Galstyan , Armen E. Allahverdyan

The joint analysis of galaxy clustering and galaxy-shear cross-correlations (galaxy-galaxy lensing) in imaging surveys constitutes one of the main avenues to obtain cosmological information. Analyses from Stage III surveys have assumed…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-03 Shivam Pandey , Carles Sánchez , Bhuvnesh Jain , The LSST Dark Energy Science Collaboration
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