Sep 8th, 2009| 10:17 am | Posted by hlee

I happened to observe a surge of principle component analysis (PCA) and independent component analysis (ICA) applications in astronomy. The PCA and ICA is used for separating mixed components with some assumptions. For the PCA, the decomposition happens by the assumption that original sources are orthogonal (uncorrelated) and mixed observations are approximated by multivariate normal distribution. For ICA, the assumptions is sources are independent and not gaussian (it grants one source component to be gaussian, though). Such assumptions allow to set dissimilarity measures and algorithms work toward maximize them. Continue reading ‘[ArXiv] component separation methods’ »

Sep 1st, 2009| 07:43 pm | Posted by hlee

[arxiv:0906.3662] **The Statistical Analysis of fMRI Data** by Martin A. Lindquist

Statistical Science, Vol. 23(4), pp. 439-464

This review paper offers some information and guidance of statistical image analysis for fMRI data that can be expanded to astronomical image data. I think that fMRI data contain similar challenges of astronomical images. As Lindquist said, collaboration helps to find shortcuts. I hope that introducing this paper helps further networking and collaboration between statisticians and astronomers.

**List of similarities** Continue reading ‘[ArXiv] Statistical Analysis of fMRI Data’ »

Tags:

data aquisition,

experimental design,

fMRI,

ICA,

image analysis,

image processing,

localization,

modeling,

pipeline,

preprocessing,

similarities,

Spatial,

temporal,

time series,

voxel Category:

arXiv,

Cross-Cultural,

Data Processing,

Imaging,

Jargon,

Methods,

Stat |

Comment
Jun 8th, 2008| 09:45 pm | Posted by hlee

Despite no statistic related discussion, a paper comparing XSPEC and ISIS, spectral analysis open source applications might bring high energy astrophysicists’ interests this week. Continue reading ‘[ArXiv] 1st week, June 2008’ »

Tags:

black box,

catalog,

CMB,

confidence interval,

EGRET,

ICA,

ISIS,

maximum likelihood,

radio,

sample size,

student t,

XSPEC Category:

arXiv,

Data Processing,

gamma-ray,

High-Energy,

Methods,

Stat |

Comment
Mar 30th, 2008| 07:51 pm | Posted by hlee

The numbers of astro-ph preprints on average have been decreased so as my hours of reading abstracts…. cool!!! By the way, there is a paper about solar cycle, PCA, ICA, and Lomb-Scargle periodogram. Continue reading ‘[ArXiv]4th week, Mar. 2008’ »

Feb 10th, 2008| 11:56 am | Posted by hlee

Review papers on Bayesian hierarchical modeling and LAR (least angle regression) appeared in this week’s stat arXiv and in addition to interesting astro-ph papers.

A review paper on LASSO and LAR: [stat.ME:0801.0964] T. Hesterberg et.al.

** Least Angle and L**_{1} Regression: A Review

Model checking for Bayesian hierarchical modeling: [stat.ME:0802.0743] M. J. Bayarri, M. E. Castellanos

** Bayesian Checking of the Second Levels of Hierarchical Models **

Continue reading ‘[ArXiv] 1st week, Feb. 2008’ »

Tags:

CMB,

compressed sensing,

cosmic void,

experimental design,

hierarchical model,

ICA,

Kd-tree,

LAR,

LASSO,

Model Selection,

solar flare,

SVM Category:

arXiv |

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