English
Related papers

Related papers: Feature importance for machine learning redshifts …

200 papers

We apply one of lazy learning methods named k-nearest neighbor algorithm (kNN) to estimate the photometric redshifts of quasars, based on various datasets from the Sloan Digital Sky Survey (SDSS), UKIRT Infrared Deep Sky Survey (UKIDSS) and…

Instrumentation and Methods for Astrophysics · Physics 2017-03-22 Zhang Yanxia , Ma He , Peng Nanbo , Zhao Yongheng , Wu Xue-bing

Redshift-space distortions (RSD), caused by the peculiar velocities of galaxies, are a key modelling challenge in galaxy clustering analyses, limiting the scales from which cosmological information can be reliably extracted. Unlike…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-31 Alexander Eggemeier , Nanoom Lee , Román Scoccimarro , Benjamin Camacho-Quevedo , Andrea Pezzotta , Martin Crocce , Ariel G. Sánchez

The unique high-resolution wide-field imaging capabilities of HST with ACS have allowed the characterization of galaxies at redshift 6, less than 1 Gyr from recombination. The dropout technique, applied to deep ACS i, z images in the RCDS…

Astrophysics · Physics 2009-11-10 Garth Illingworth , Rychard Bouwens

We present a novel, domain-agnostic, model-independent, unsupervised, and universally applicable Machine Learning approach for dimensionality reduction based on the principles of algorithmic complexity. Specifically, but without loss of…

Data Structures and Algorithms · Computer Science 2025-05-06 Hector Zenil , Narsis A. Kiani , Alyssa Adams , Felipe S. Abrahão , Antonio Rueda-Toicen , Allan A. Zea , Luan Ozelim , Jesper Tegnér

The Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) will produce several billion photometric redshifts (photo-$z$'s), enabling cosmological analyses to select a subset of galaxies with the most accurate photo-$z$. We…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-08 Adam Broussard , Eric Gawiser

A goal of forthcoming imaging surveys is to use weak gravitational lensing shear measurements to constrain dark energy. We quantify the importance of uncalibrated photometric redshift outliers to the dark energy goals of forthcoming imaging…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Andrew P. Hearin , Andrew R. Zentner , Zhaoming Ma , Dragan Huterer

We created a catalog of photometric redshift of ~3,000,000 SDSS galaxies annotated by their broad morphology. The photometric redshift was optimized by testing and comparing several pattern recognition algorithms and variable selection…

Astrophysics of Galaxies · Physics 2018-06-12 Nicholas Paul , Nicholas Virag , Lior Shamir

With the decreasing cost of data collection, the space of variables or features that can be used to characterize a particular predictor of interest continues to grow exponentially. Therefore, identifying the most characterizing features…

Machine Learning · Computer Science 2021-01-26 Sali Rasoul , Sodiq Adewole , Alphonse Akakpo

In this study, we develop an artificial neural network to estimate the infrared (IR) luminosity and star formation rates (SFR) of galaxies. Our network is trained using 'true' IR luminosity values derived from modeling the IR spectral…

Astrophysics of Galaxies · Physics 2024-12-24 Ashraf Ayubinia , Jong-hak Woo , Fatemeh Hafezianzadeh , Taehwan Kim , Changseok Kim

We present a new approach to obtaining photometric redshifts using a kernel learning technique called Support Vector Machines (SVMs). Unlike traditional spectral energy distribution fitting, this technique requires a large and…

Astrophysics · Physics 2009-11-10 Yogesh Wadadekar

We present a novel way of using neural networks (NN) to estimate the redshift distribution of a galaxy sample. We are able to obtain a probability density function (PDF) for each galaxy using a classification neural network. The method is…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-08 Christopher Bonnett

Galaxy groups are essential for studying the distribution of matter on a large scale in redshift surveys and for deciphering the link between galaxy traits and their associated halos. In this work, we propose a widely applicable method for…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-03 Juntao Ma , Jie Wang , Tianxiang Mao , Hongxiang Chen , Yuxi Meng , Xiaohu Yang , Qingyang Li

In the next decade, the LSST will become a major facility for the astronomical community. However accurately determining the redshifts of the observed galaxies without using spectroscopy is a major challenge. Reconstruction of the redshifts…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Alexia Gorecki , Alexandra Abate , Réza Ansari , Aurélien Barrau , Sylvain Baumont , Marc Moniez , Jean-Stéphane Ricol

We use the Random Forest (RF) algorithm to develop a tool for automated activity classification of galaxies into 5 different classes: Star-forming (SF), AGN, LINER, Composite, and Passive. We train the algorithm on a combination of mid-IR…

Astrophysics of Galaxies · Physics 2023-03-22 Elias Kyritsis , Charalampos Daoutis , Andreas Zezas , Konstantinos Kouroumpatzakis

We analyze the behaviors of reddening vectors in the SDSS photometric system for galaxies of different morphologies, ages, and redshifts. As seen in other photometric systems, the dependence of reddening on the spectral energy distribution…

Astrophysics · Physics 2009-11-13 Sungsoo S. Kim , Myung Gyoon Lee

Wide-field slitless spectroscopic galaxy surveys, such as the one performed by the upcoming Chinese Space Station Survey Telescope (CSST), are crucial for precision cosmology but present formidable data analysis challenges. Because spectra…

Instrumentation and Methods for Astrophysics · Physics 2026-05-19 Xingchen Zhou , Yan Gong , Xin Zhang , Xian-Min Meng , Haitao Miao , Run Wen , Nan Li

The development of noninvasive brain imaging such as resting-state functional magnetic resonance imaging (rs-fMRI) and its combination with AI algorithm provides a promising solution for the early diagnosis of Autism spectrum disorder…

Image and Video Processing · Electrical Eng. & Systems 2022-04-11 Fangyu Zhang , Yanjie Wei , Jin Liu , Yanlin Wang , Wenhui Xi , Yi Pan

We develop a cosmological parameter estimation code for (tomographic) angular power spectra analyses of galaxy number counts, for which we include, for the first time, redshift-space distortions (RSD) in the Limber approximation. This…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-15 Konstantinos Tanidis , Stefano Camera

The acute respiratory distress syndrome (ARDS) is a severe form of hypoxemic respiratory failure with in-hospital mortality of 35-46%. High mortality is thought to be related in part to challenges in making a prompt diagnosis, which may in…

Machine Learning · Computer Science 2021-09-28 Gregory B. Rehm , Chao Wang , Irene Cortes-Puch , Chen-Nee Chuah , Jason Adams