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Related papers: PHAT: PHoto-z Accuracy Testing

200 papers

Aims. We analyse the relative performance of different photo-z codes in blind applications to ground-based data. Methods. We tested the codes on imaging datasets with different depths and filter coverages and compared the results to large…

Astrophysics · Physics 2009-11-13 H. Hildebrandt , C. Wolf , N. Benitez

A precise measurement of photometric redshifts (photo-z) is key for the success of modern photometric galaxy surveys. Machine learning (ML) methods show great promise in this context, but suffer from covariate shift (CS) in training sets…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-19 Chiara Moretti , Maximilian Autenrieth , Riccardo Serra , Roberto Trotta , David A. van Dyk , Andrei Mesinger

We describe a new test of photometric redshift performance given a spectroscopic redshift sample. This test complements the traditional comparison of redshift {\it differences} by testing whether the probability density functions $p(z)$…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 David Wittman , Ramya Bhaskar , Ryan Tobin

Context. Accurate photometric redshift estimation is crucial for cosmological and galaxy evolution studies, especially with the advent of large-scale photometric surveys. Aims. We developed a photo-z estimation code called TOPz (Tartu…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-26 E. Tempel , J. Laur , Z. R. Jones , R. Kipper , L. J. Liivamägi , D. Pandey , G. Sakteos , A. Tamm , A. N. Triantafyllaki , T. Tuvikene

The PHOT (Portable High-Speed Occultation Telescope) systems were developed for the specific purpose of observing stellar occultations by solar system objects. Stellar occultations have unique observing constraints: they may only be…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 E. F. Young , L. A. Young , C. B. Olkin , K. Shoemaker , R. G. French , J. Regester , M. W. Buie

Photometric galaxy surveys are an essential tool to further our understanding of the large-scale structure of the universe, its matter and energy content and its evolution. These surveys necessitate the determination of the galaxy redshifts…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-06 Pol Martí , Ramon Miquel , Anne Bauer , Enrique Gaztañaga

We describe a new program for determining photometric redshifts, dubbed EAZY. The program is optimized for cases where spectroscopic redshifts are not available, or only available for a biased subset of the galaxies. The code combines…

Astrophysics · Physics 2009-11-13 Gabriel B. Brammer , Pieter G. van Dokkum , Paolo Coppi

The Potts model is frequently used to describe the behavior of image classes, since it allows to incorporate contextual information linking neighboring pixels in a simple way. Its isotropic version has only one real parameter beta, known as…

Applications · Statistics 2014-05-08 J. Gimenez , A. C. Frery , Ana Georgina Flesia

Machine learning photo-z methods, trained directly on spectroscopic redshifts, provide a viable alternative to traditional template fitting methods but may not generalise well on new data that deviates from that in the training set. In this…

Instrumentation and Methods for Astrophysics · Physics 2024-02-02 Shingo Tanigawa , Karl Glazebrook , Colin Jacobs , Ivo Labbe , Alex K. Qin

Pareto distributions are widely used models in economics, finance and actuarial sciences. As a result, a number of goodness-of-fit tests have been proposed for these distributions in the literature. We provide an overview of the existing…

Methodology · Statistics 2022-11-21 L. Ndwandwe , J. S. Allison , L. Santana , I. J. H. Visagie

Previous studies determining which astronomical photometry software is best suited for a particular dataset are usually focused on speed, source classification, and/or meeting a sensitivity requirement. For faint objects in particular, the…

Instrumentation and Methods for Astrophysics · Physics 2013-05-27 Sarah Sonnett , Karen Meech , Robert Jedicke , Schelte Bus , John Tonry , Olivier Hainaut

In this paper we introduce the \textsc{Deepz} deep learning photometric redshift (photo-$z$) code. As a test case, we apply the code to the PAU survey (PAUS) data in the COSMOS field. \textsc{Deepz} reduces the $\sigma_{68}$ scatter…

Recognising and locating image patches or sets of image features is an important task underlying much work in computer vision. Traditionally this has been accomplished using template matching. However, template matching is notoriously…

Computer Vision and Pattern Recognition · Computer Science 2025-01-22 M. W. Spratling

Photoacoustic tomography (PAT) is a medical imaging modality that can provide high-resolution tissue images based on the optical absorption. Classical reconstruction methods for quantifying the absorption coefficients rely on sufficient…

Image and Video Processing · Electrical Eng. & Systems 2026-04-24 Anssi Manninen , Janek Gröhl , Felix Lucka , Andreas Hauptmann

Test-time adaptation (TTA) has emerged as a promising paradigm for vision-language models (VLMs) to bridge the distribution gap between pre-training and test data. Recent works have focused on backpropagation-free TTA methods that rely on…

Computer Vision and Pattern Recognition · Computer Science 2026-05-14 Zhaohong Huang , Yuxin Zhang , Wenjing Liu , Fei Chao , Rongrong Ji

Towards predicting patch correctness in APR, we propose a simple, but novel hypothesis on how the link between the patch behaviour and failing test specifications can be drawn: similar failing test cases should require similar patches. We…

Software Engineering · Computer Science 2022-03-17 Haoye Tian , Yinghua Li , Weiguo Pian , Abdoul Kader Kaboré , Kui Liu , Andrew Habib , Jacques Klein , Tegawendé F. Bissyande

Evaluating anomaly detection algorithms in time series data is critical as inaccuracies can lead to flawed decision-making in various domains where real-time analytics and data-driven strategies are essential. Traditional performance…

Machine Learning · Computer Science 2024-05-21 Ramin Ghorbani , Marcel J. T. Reinders , David M. J. Tax

The accurate estimation of photometric redshifts is crucial to many upcoming galaxy surveys, for example the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST). Almost all Rubin extragalactic and cosmological science requires…

Instrumentation and Methods for Astrophysics · Physics 2022-05-04 Natalia Stylianou , Alex I. Malz , Peter Hatfield , John Franklin Crenshaw , Julia Gschwend

This work is concerned with uncertainty quantification problems for image reconstructions in quantitative photoacoustic imaging (PAT), a recent hybrid imaging modality that utilizes the photoacoustic effect to achieve high-resolution…

Numerical Analysis · Mathematics 2018-12-10 Kui Ren , Sarah Vallélian
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