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Bayesian Inference is a powerful approach to data analysis that is based almost entirely on probability theory. In this approach, probabilities model {\it uncertainty} rather than randomness or variability. This thesis is composed of a…

Astrophysics · Physics 2008-09-08 Brendon J. Brewer

Magnification bias, an observational effect of gravitational lensing in the weak regime, allows testing the cosmological model through angular correlations of sources at different redshifts. This effect has been observed in various…

Galaxy cluster number counts are an important probe to constrain cosmological parameters. One of the main ingredients of the analysis, along with accurate estimates of the clusters' masses, is the selection function, and in particular the…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-29 Stefano Gallo , Marian Douspis , Elie Soubrié , Laura Salvati

Cosmology analyses using galaxy clusters by the Dark Energy Survey have recently uncovered an issue of previously unknown selection effect affecting weak lensing mass estimates. In this letter, we use the Illustris-TNG simulation to…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-26 Yuanyuan Zhang , James Annis

In cluster analysis interest lies in probabilistically capturing partitions of individuals, items or observations into groups, such that those belonging to the same group share similar attributes or relational profiles. Bayesian posterior…

Methodology · Statistics 2017-03-23 Riccardo Rastelli , Nial Friel

We have evaluated a systematic effect on counts-in-cells analysis of deep, wide-field galaxy catalogues induced by the evolution of clustering within the survey volume. A multiplicative correction factor is explicitly presented, which can…

Astrophysics · Physics 2009-10-30 Takahiko Matsubara , Yasushi Suto , Istvan Szapudi

This paper examines several methods of tracing galaxies in N-body simulations and their effects on the derived galaxy statistics, especially measurements of velocity bias. Using two simulations with identical initial conditions, one…

Astrophysics · Physics 2009-06-16 F J Summers , Marc Davis , August E. Evrard

Galaxy clusters are an established and powerful test-bed for theories of both galaxy evolution and cosmology. Accurate interpretation of cluster observations often requires robust identification of the location of the centre. Using a…

The world is not static: This causes real-world time series to change over time through external, and potentially disruptive, events such as macroeconomic cycles or the COVID-19 pandemic. We present an adaptive sampling strategy that…

Large galaxies are thought to form hierarchically, from the accretion and disruption of many smaller galaxies. Such a scenario should naturally lead to galactic phase-space distributions containing some degree of substructure. We examine…

Astrophysics · Physics 2009-11-11 Brian M. Yencho , Kathryn V. Johnston , James S. Bullock , Katherine L. Rhode

Standard maximum-likelihood estimators for binary-star and exoplanet eccentricities are biased high, in the sense that the estimated eccentricity tends to be larger than the true eccentricity. As with most non-trivial observables, a simple…

Solar and Stellar Astrophysics · Physics 2011-01-19 David W. Hogg , Adam D. Myers , Jo Bovy

Connecting galaxies with their descendants (or progenitors) at different redshifts can yield strong constraints on galaxy evolution. Observational studies have historically selected samples of galaxies using a physical quantity, such as…

Astrophysics of Galaxies · Physics 2015-05-20 Carl J. Mundy , Christopher J. Conselice , Jamie R. Ownsworth

Cosmological simulations are a powerful tool to advance our understanding of galaxy formation and many simulations model key properties of real galaxies. A question that naturally arises for such simulations in light of high-quality…

Astrophysics of Galaxies · Physics 2025-09-10 Lingyi Zhou , Stefan T. Radev , William H. Oliver , Aura Obreja , Zehao Jin , Tobias Buck

The angular power spectrum is a natural tool to analyse the observed galaxy number count fluctuations. In a standard analysis, the angular galaxy distribution is sliced into concentric redshift bins and all correlations of its harmonic…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-14 Guglielmo Faggioli , Konstantinos Tanidis , Stefano Camera

Obtaining robust galaxy number counts is crucial for understanding galaxy evolution, and submillimetre counts in particular have proven valuable for revising subgrid physics models in cosmological simulations. In confusion-limited surveys,…

Astrophysics of Galaxies · Physics 2026-05-12 Yunting Wang , Ryley Hill , Douglas Scott , Tessa Vernstrom

Counts in cells are used to analyse the higher order properties of the statistics of the EDSGC survey. The probability distribution is obtained from an equal area projection source catalog with infinite oversampling over the range…

Astrophysics · Physics 2009-10-28 István Szapudi , Avery Meiksin , Robert C. Nichol

We derive a family of loss functions to train models in the presence of sampling bias. Examples are when the prevalence of a pathology differs from its sampling rate in the training dataset, or when a machine learning practioner rebalances…

In Bayesian theory, calculating a posterior probability distribution is highly important but usually difficult. Therefore, some methods have been put forward to deal with such problem, among which, the most popular one is the asymptotic…

Methodology · Statistics 2012-07-20 Zai-Ying Zhou

If the prior probability distributions of all possible hypothetical true means and all possible observed means of a continuous variable are conditional on the universal set of all numbers (i.e., before the nature of a study is known and a…

Methodology · Statistics 2025-06-05 Huw Llewelyn

Density deconvolution is the task of estimating a probability density function given only noise-corrupted samples. We can fit a Gaussian mixture model to the underlying density by maximum likelihood if the noise is normally distributed, but…

Machine Learning · Statistics 2020-07-14 Tim Dockhorn , James A. Ritchie , Yaoliang Yu , Iain Murray