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Related papers: Clustered Radio Interferometric Calibration

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With the inflation of the data, clustering analysis, as a branch of unsupervised learning, lacks unified understanding and application of its mathematical law. Based on the view of fixed point, this paper restates the model-based clustering…

Machine Learning · Computer Science 2020-02-20 Jianhao Ding , Lansheng Han

Quality assessments of models in unsupervised learning and clustering verification in particular have been a long-standing problem in the machine learning research. The lack of robust and universally applicable cluster validity scores often…

Machine Learning · Statistics 2018-03-30 Luzie Helfmann , Johannes von Lindheim , Mattes Mollenhauer , Ralf Banisch

This paper develops procedures to combine clusters for the approximate randomization test proposed by Canay, Romano, and Shaikh (2017). Their test can be used to conduct inference with a small number of clusters and imposes weak…

Econometrics · Economics 2025-02-07 Chun Pong Lau

Flux calibration of spectra in reverberation mapping (RM) is most often performed by assuming the flux constancy of some specified narrow emission lines, which stem from an extended region that is sometimes partially spatially resolved, in…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Yan-Rong Li , Jian-Min Wang , Chen Hu , Pu Du , Jin-Ming Bai

Clustering data objects into homogeneous groups is one of the most important tasks in data mining. Spectral clustering is arguably one of the most important algorithms for clustering, as it is appealing for its theoretical soundness and is…

Machine Learning · Statistics 2024-03-12 Dylan Soemitro , Jeova Farias Sales Rocha Neto

A novel and intuitive nearest neighbours based clustering algorithm is introduced, in which a cluster is defined in terms of an equilibrium condition which balances its size and cohesiveness. The formulation of the equilibrium condition…

Machine Learning · Computer Science 2025-03-31 David P. Hofmeyr

This paper presents a novel non-rigid point set registration method that is inspired by unsupervised clustering analysis. Unlike previous approaches that treat the source and target point sets as separate entities, we develop a holistic…

Computer Vision and Pattern Recognition · Computer Science 2024-06-28 Mingyang Zhao , Jingen Jiang , Lei Ma , Shiqing Xin , Gaofeng Meng , Dong-Ming Yan

We present stacking polarized intensity as a means to study the polarization of sources that are too faint to be detected individually in surveys of polarized radio sources. Stacking offers not only high sensitivity to the median signal of…

Astrophysics of Galaxies · Physics 2015-06-19 J. M. Stil , B. W. Keller , S. J. George , A. R. Taylor

This paper investigates the possibility of improving radio interferometric images using an algorithm inspired by an optical method known as "lucky imaging", which would give more weight to the best-calibrated visibilities used to make a…

Instrumentation and Methods for Astrophysics · Physics 2018-07-18 Etienne Bonnassieux , Cyril Tasse , Oleg Smirnov , Philippe Zarka

Compact interferometers, called phasemeters, make it possible to operate over a large range while ensuring a high resolution. Such performance is required for the stabilization of large instruments dedicated to experimental physics such as…

Instrumentation and Methods for Astrophysics · Physics 2018-12-03 Jennifer Watchi , Sam Cooper , Binlei Ding , Conor M. Mow-Lowry , Christophe Collette

Using radio sources from the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey, and optical counterparts in the Sloan Digital Sky Survey (SDSS), we have identified a large number of galaxy clusters. The radio sources within these…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-03 Joshua D. Wing , Elizabeth L. Blanton

This paper proposes the use of "multicalibration" to yield interpretable and reliable confidence scores for outputs generated by large language models (LLMs). Multicalibration asks for calibration not just marginally, but simultaneously…

Machine Learning · Statistics 2024-04-09 Gianluca Detommaso , Martin Bertran , Riccardo Fogliato , Aaron Roth

This paper presents a clustering approach that allows for rigorous statistical error control similar to a statistical test. We develop estimators for both the unknown number of clusters and the clusters themselves. The estimators depend on…

Statistics Theory · Mathematics 2017-07-13 Michael Vogt , Matthias Schmid

This paper presents Constrained Centroid Clustering (CCC), a method that extends classical centroid-based clustering by enforcing a constraint on the maximum distance between the cluster center and the farthest point in the cluster. Using a…

Machine Learning · Computer Science 2025-08-19 Sowmini Devi Veeramachaneni , Ramamurthy Garimella

In an age of increasingly large data sets, investigators in many different disciplines have turned to clustering as a tool for data analysis and exploration. Existing clustering methods, however, typically depend on several nontrivial…

Quantitative Methods · Quantitative Biology 2009-11-11 Noam Slonim , Gurinder Singh Atwal , Gasper Tkacik , William Bialek

Clustering of mixed-type datasets can be a particularly challenging task as it requires taking into account the associations between variables with different level of measurement, i.e., nominal, ordinal and/or interval. In some cases,…

Methodology · Statistics 2022-04-22 Odysseas Moschidis , Angelos Markos , Theodore Chadjipadelis

We consider quantizing an $Ld$-dimensional sample, which is obtained by concatenating $L$ vectors from datasets of $d$-dimensional vectors, to a $d$-dimensional cluster center. The distortion measure is the weighted sum of $r$th powers of…

Machine Learning · Computer Science 2020-10-26 Erdem Koyuncu

We present a method for subtracting point sources from interferometric radio images via forward modeling of the instrument response and involving an algebraic nonlinear minimization. The method is applied to simulated maps of the Murchison…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. Bernardi , D. A. Mitchell , S. M. Ord , L. J. Greenhill , B. Pindor , R. B. Wayth , J. S. B. Wyithe

We devise a fast and optimal estimator for the amplitude of the bispectrum of clustered Infrared (IR) point-sources. We show how this estimator can account for the cases of partial sky coverage and inhomogeneous noise. Expected detection…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-24 F. Lacasa , N. Aghanim

Sensor calibration is an indispensable task in any networked cyberphysical system. In this paper, we consider a sensor network plagued with offset errors, measuring a rank-1 signal subspace, where each sensor collects measurements under a…

Signal Processing · Electrical Eng. & Systems 2023-12-14 Raj Thilak Rajan