Sep 25th, 2009| 01:24 pm | Posted by hlee

By accident, a piece of paper was found from my old text book. I have no idea who wrote this, nor how old it is. Too old to be obsolete? But it has general description to become a good person and scientist Continue reading ‘To Become a Good Astronomer’ »

Sep 22nd, 2009| 12:03 pm | Posted by hlee

Thanks to a Korean solar physicist^{[1]} I was able to gather the following websites and some relevant information on Space Weather Forecast in action, not limited to literature nor toy data.

Continue reading ‘More on Space Weather’ »

Tags:

automatic,

CME,

computer vision,

data mining,

feature detection,

filament,

image processing,

machine learning,

manifold,

space weather,

statistical learning,

sunspot,

SVM Category:

Algorithms,

arXiv,

Cross-Cultural,

Data Processing,

Imaging,

Jargon |

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Sep 11th, 2009| 03:40 pm | Posted by hlee

A number of practical Bayesian data analysis books are available these days. Here, I’d like to introduce two that were relatively recently published. I like the fact that they are rather technical than theoretical. They have practical examples close to be related with astronomical data. They have R codes so that one can try algorithms on the fly instead of jamming probability theories. Continue reading ‘[Books] Bayesian Computations’ »

Tags:

book,

BUGS,

CMB,

examples,

HMM,

identifiability,

image processing,

LLN,

mixture,

MRF,

R Category:

Bayesian,

Fitting,

Languages,

MC,

MCMC,

Methods,

Stat |

1 Comment
Sep 10th, 2009| 11:20 pm | Posted by hlee

Soon it’ll not be qualified for [MADS] because I saw some abstracts with the phrase, **compressed sensing** from arxiv.org. Nonetheless, there’s one publication within refereed articles from ADS, so far.

http://adsabs.harvard.edu/abs/2009MNRAS.395.1733W.

*Title:***Compressed sensing imaging techniques for radio interferometry**

*Authors:* Wiaux, Y. et al. Continue reading ‘[MADS] compressed sensing’ »

Tags:

compressed sensing,

ill-posed,

image reconstruction,

interferometry,

inverse problem,

MADS,

Nyquist-Shannon sampling theorem Category:

Algorithms,

Cross-Cultural,

Data Processing,

Imaging,

Jargon,

Spectral |

Comment
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 4th, 2009| 01:30 pm | Posted by hlee

ARCH (**autoregressive conditional heteroscedasticity**) is a statistical model that considers *the variance of the current error term to be a function of the variances of the previous time periods’ error terms*. I heard that this model made Prof. Engle a Nobel prize recipient. Continue reading ‘[MADS] ARCH’ »

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 |

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