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Related papers: Mixture Models in Astronomy

200 papers

A mixture of variance-gamma distributions is introduced and developed for model-based clustering and classification. The latest in a growing line of non-Gaussian mixture approaches to clustering and classification, the proposed mixture of…

Methodology · Statistics 2014-12-30 Sharon M. McNicholas , Paul D. McNicholas , Ryan P. Browne

Current analysis of astronomical data are confronted with the daunting task of modeling the awkward features of astronomical data, among which heteroscedastic (point-dependent) errors, intrinsic scatter, non-ignorable data collection…

Instrumentation and Methods for Astrophysics · Physics 2011-12-19 S. Andreon

Mixture models provide a flexible representation of heterogeneity in a finite number of latent classes. From the Bayesian point of view, Markov Chain Monte Carlo methods provide a way to draw inferences from these models. In particular,…

Methodology · Statistics 2020-05-06 Carolina Valani Cavalcante , Kelly Cristina Mota Gonçalves

In many evolutionary stages, low- and intermediate-mass stars show signs of mixing of the surface material with material from the interior. To account for all the details revealed by the observations it is necessary to include non-standard…

Solar and Stellar Astrophysics · Physics 2011-07-01 Rodolfo Smiljanic

Clustering is a widely used technique in data mining applications for discovering patterns in underlying data. Most traditional clustering algorithms are limited to handling datasets that contain either numeric or categorical attributes.…

Artificial Intelligence · Computer Science 2007-05-23 Zengyou He , Xiaofei Xu , Shengchun Deng

A mixture of multivariate contaminated normal (MCN) distributions is a useful model-based clustering technique to accommodate data sets with mild outliers. However, this model only works when fitted to complete data sets, which is often not…

Methodology · Statistics 2020-12-11 Hung Tong , Cristina Tortora

Mixture models whose components have skewed hypercube contours are developed via a generalization of the multivariate shifted asymmetric Laplace density. Specifically, we develop mixtures of multiple scaled shifted asymmetric Laplace…

Methodology · Statistics 2023-03-28 Brian C. Franczak , Cristina Tortora , Ryan P. Browne , Paul D. McNicholas

Hierarchical clustering is a common algorithm in data analysis. It is unique among many clustering algorithms in that it draws dendrograms based on the distance of data under a certain metric, and group them. It is widely used in all areas…

Instrumentation and Methods for Astrophysics · Physics 2022-11-14 Heng Yu , Xiaolan Hou

Forthcoming large galaxy cluster surveys will yield tight constraints on cosmological models. It has been shown that in an idealized survey, containing > 10,000 clusters, statistical errors on dark energy and other cosmological parameters…

Astrophysics · Physics 2008-11-26 Joshua D. Younger , Zoltan Haiman , Greg L. Bryan , Sheng Wang

The Dirichlet process mixture model and more general mixtures based on discrete random probability measures have been shown to be flexible and accurate models for density estimation and clustering. The goal of this paper is to illustrate…

Methodology · Statistics 2013-10-02 Ernesto Barrios , Antonio Lijoi , Luis E. Nieto-Barajas , Igor Prünster

Cluster analysis of biological samples using gene expression measurements is a common task which aids the discovery of heterogeneous biological sub-populations having distinct mRNA profiles. Several model-based clustering algorithms have…

Methodology · Statistics 2012-01-30 Alberto Cozzini , Ajay Jasra , Giovanni Montana

Present and future large scale surveys offer promising probes of cosmology. For example the Dark Energy Survey (DES) is forecast to detect ~300 millions galaxies and thousands clusters up to redshift ~1.3. I here show ongoing work to…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-07 Fabien Lacasa

The mixture models have become widely used in clustering, given its probabilistic framework in which its based, however, for modern databases that are characterized by their large size, these models behave disappointingly in setting out the…

Machine Learning · Statistics 2017-02-01 Abdelghafour Talibi , Boujemâa Achchab , Rafik Lasri

Clustering mixed data presents numerous challenges inherent to the very heterogeneous nature of the variables. A clustering algorithm should be able, despite of this heterogeneity, to extract discriminant pieces of information from the…

Machine Learning · Computer Science 2022-05-10 Robin Fuchs , Denys Pommeret , Cinzia Viroli

Since the early 1970s, stellar population modelling has been one of the basic tools for understanding the physics of unresolved systems from observation of their integrated light. Models allow us to relate the integrated spectra (or…

Instrumentation and Methods for Astrophysics · Physics 2013-12-03 Miguel Cerviño

Machine learning, algorithms to extract empirical knowledge from data, can be used to classify data, which is one of the most common tasks in observational astronomy. In this paper, we focus on Bayesian data classification algorithms using…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 K. J. Lee , L. Guillemot , Y. L. Yue , M. Kramer , D. J. Champion

Clustering task of mixed data is a challenging problem. In a probabilistic framework, the main difficulty is due to a shortage of conventional distributions for such data. In this paper, we propose to achieve the mixed data clustering with…

Methodology · Statistics 2015-10-01 Matthieu Marbac , Christophe Biernacki , Vincent Vandewalle

Given a random sample of observations, mixtures of normal densities are often used to estimate the unknown continuous distribution from which the data come. Here we propose the use of this semiparametric framework for testing symmetry about…

Methodology · Statistics 2012-04-23 Silvia Bacci , Francesco Bartolucci

The clustering of galaxy clusters is a powerful cosmological tool, which can help to break degeneracies between parameters when combined with other cosmological observables. We aim to demonstrate its potential in constraining cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-16 Alessandra Fumagalli , Matteo Costanzi , Alexandro Saro , Tiago Castro , Stefano Borgani

Astronomical observations typically provide three-dimensional maps, encoding the distribution of the observed flux in (1) the two angles of the celestial sphere and (2) energy/frequency. An important task regarding such maps is to…

Instrumentation and Methods for Astrophysics · Physics 2024-01-09 Florian Wolf , Florian List , Nicholas L. Rodd , Oliver Hahn