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Direct detection of the Epoch of Reionization via the redshifted 21-cm line will have unprecedented implications on the study of structure formation in the early Universe. To fulfill this promise current and future 21-cm experiments will…

宇宙学与河外天体物理 · 物理学 2018-08-22 F. Mertens , A. Ghosh , L. V. E. Koopmans

A critical challenge in measuring the power spectrum of 21cm emission from cosmic reionization is compensating for the frequency dependence of an interferometer's sampling pattern, which can cause smooth-spectrum foregrounds to appear…

天体物理仪器与方法 · 物理学 2015-06-04 Aaron R. Parsons , Jonathan C. Pober , James E. Aguirre , Christopher L. Carilli , Daniel C. Jacobs , David F. Moore

Principal component analysis has been widely adopted to reduce the dimension of data while preserving the information. The quantum version of PCA (qPCA) can be used to analyze an unknown low-rank density matrix by rapidly revealing the…

量子物理 · 物理学 2022-01-26 Zhaokai Li , Zihua Chai , Yuhang Guo , Wentao Ji , Mengqi Wang , Fazhan Shi , Ya Wang , Seth Lloyd , Jiangfeng Du

We propose kernel PCA as a method for analyzing the dependence structure of multivariate extremes and demonstrate that it can be a powerful tool for clustering and dimension reduction. Our work provides some theoretical insight into the…

机器学习 · 统计学 2022-11-28 Marco Avella-Medina , Richard A. Davis , Gennady Samorodnitsky

The high-dimensional feature space of the hyperspectral imagery poses major challenges to the processing and analysis of the hyperspectral data sets. In such a case, dimensionality reduction is necessary to decrease the computational…

图像与视频处理 · 电气工程与系统科学 2024-06-06 Mustafa Ustuner

Machine learning (ML) methods have proved to be a very successful tool in physical sciences, especially when applied to experimental data analysis. Artificial intelligence is particularly good at recognizing patterns in high dimensional…

Aims: We show the use of principal component analysis (PCA) and Fourier decomposition (FD) method as tools for variable star diagnostics and compare their relative performance in studying the changes in the light curve structures of…

太阳与恒星天体物理 · 物理学 2015-05-13 Sukanta Deb , Harinder P. Singh

Principal Component Analysis (PCA) has wide applications in machine learning, text mining and computer vision. Classical PCA based on a Gaussian noise model is fragile to noise of large magnitude. Laplace noise assumption based PCA methods…

机器学习 · 计算机科学 2014-12-22 Pengtao Xie , Eric Xing

Constructing an efficient parameterization of a large, noisy data set of points lying close to a smooth manifold in high dimension remains a fundamental problem. One approach consists in recovering a local parameterization using the local…

数据分析、统计与概率 · 物理学 2013-12-09 Daniel N. Kaslovsky , Francois G. Meyer

Power spectrum estimators are an important tool in efforts to detect the 21 cm brightness temperature fluctuations from neutral hydrogen at early times. An initial detection will likely be statistical in nature, meaning that it will not be…

宇宙学与河外天体物理 · 物理学 2024-10-24 Jacob Burba , Philip Bull , Michael J. Wilensky , Fraser Kennedy , Hugh Garsden , Katrine A. Glasscock

We use full sky simulations, including the effects of foreground contamination and removal, to explore multi-tracer synergies between a SKA-like 21cm intensity mapping survey and a LSST-like photometric galaxy redshift survey. In particular…

宇宙学与河外天体物理 · 物理学 2019-03-27 Amadeus Witzemann , David Alonso , José Fonseca , Mario G. Santos

Principal Component Analysis (PCA) is an efficient tool to optimize the multiparameter tests of general relativity (GR) where one tests for simultaneous deviations in multiple post-Newtonian (PN) phasing coefficients by introducing…

广义相对论与量子宇宙学 · 物理学 2022-08-17 Sayantani Datta , M. Saleem , K. G. Arun , B. S. Sathyaprakash

Principal Component Analysis (PCA) is the most common nonparametric method for estimating the volatility structure of Gaussian interest rate models. One major difficulty in the estimation of these models is the fact that forward rate curves…

统计金融 · 定量金融 2014-08-28 Marcio Laurini , Alberto Ohashi

This work studies estimation of sparse principal components in high dimensions. Specifically, we consider a class of estimators based on kernel PCA, generalizing the covariance thresholding algorithm proposed by Krauthgamer et al. (2015).…

统计理论 · 数学 2025-04-10 Michael J. Feldman , Theodor Misiakiewicz , Elad Romanov

In the context of difference image analysis (DIA), we present a new method for determining the convolution kernel matching a pair of images of the same field. Unlike the standard DIA technique which involves modelling the kernel as a linear…

天体物理学 · 物理学 2009-11-13 D. M. Bramich

Calcium imaging is an essential tool to study the activity of neuronal populations. However, the high level of background fluorescence in images hinders the accurate identification of neurons and the extraction of neuronal activities. While…

图像与视频处理 · 电气工程与系统科学 2021-08-05 Seungjae Han , Eun-Seo Cho , Inkyu Park , Kijung Shin , Young-Gyu Yoon

We study the problem of high-dimensional Principal Component Analysis (PCA) with missing observations. In simple, homogeneous missingness settings with a noise level of constant order, we show that an existing inverse-probability weighted…

统计方法学 · 统计学 2019-07-01 Ziwei Zhu , Tengyao Wang , Richard J. Samworth

Cyber security threats have been growing significantly in both volume and sophistication over the past decade. This poses great challenges to malware detection without considerable automation. In this paper, we have proposed a novel…

密码学与安全 · 计算机科学 2019-02-12 Jason Zhang

Long video generation involves generating extended videos using models trained on short videos, suffering from distribution shifts due to varying frame counts. It necessitates the use of local information from the original short frames to…

计算机视觉与模式识别 · 计算机科学 2025-05-05 Jiangtong Tan , Hu Yu , Jie Huang , Jie Xiao , Feng Zhao

We study Principal Component Analysis (PCA) in a setting where a part of the corrupting noise is data-dependent and, as a result, the noise and the true data are correlated. Under a bounded-ness assumption on the true data and the noise,…

信息论 · 计算机科学 2017-11-01 Namrata Vaswani , Praneeth Narayanamurthy