The AstroStat Slog » consistency http://hea-www.harvard.edu/AstroStat/slog Weaving together Astronomy+Statistics+Computer Science+Engineering+Intrumentation, far beyond the growing borders Fri, 09 Sep 2011 17:05:33 +0000 en-US hourly 1 http://wordpress.org/?v=3.4 [ArXiv] 2nd week, Jan. 2007 http://hea-www.harvard.edu/AstroStat/slog/2008/arxiv-2nd-week-jan-2007/ http://hea-www.harvard.edu/AstroStat/slog/2008/arxiv-2nd-week-jan-2007/#comments Fri, 11 Jan 2008 19:44:44 +0000 hlee http://hea-www.harvard.edu/AstroStat/slog/2008/arxiv-2nd-week-jan-2007/ It is notable that there’s an astronomy paper contains AIC, BIC, and Bayesian evidence in the title. The topic of the paper, unexceptionally, is cosmology like other astronomy papers discussed these (statistical) information criteria (I only found a couple of papers on model selection applied to astronomical data analysis without articulating CMB stuffs. Note that I exclude Bayes factor for the model selection purpose).

To find the paper or other interesting ones, click

  • [astro-ph:0801.0638]
    AIC, BIC, Bayesian evidence and a notion on simplicity of cosmological model M Szydlowski & A. Kurek

  • [astro-ph:0801.0642]
    Correlation of CMB with large-scale structure: I. ISW Tomography and Cosmological Implications S. Ho et.al.

  • [astro-ph:0801.0780]
    The Distance of GRB is Independent from the Redshift F. Song

  • [astro-ph:0801.1081]
    A robust statistical estimation of the basic parameters of single stellar populations. I. Method X. Hernandez and D. Valls–Gabaud

  • [astro-ph:0801.1106]
    A Catalog of Local E+A(post-starburst) Galaxies selected from the Sloan Digital Sky Survey Data Release 5 T. Goto (Carefully built catalogs are wonderful sources for classification/supervised learning, or semi-supervised learning)

  • [astro-ph:0801.1358]
    A test of the Poincare dodecahedral space topology hypothesis with the WMAP CMB data B.S. Lew & B.F. Roukema

In cosmology, a few candidate models to be chosen, are generally nested. A larger model usually is with extra terms than smaller ones. How to define the penalty for the extra terms will lead to a different choice of model selection criteria. However, astronomy papers in general never discuss the consistency or statistical optimality of these selection criteria; most likely Monte Carlo simulations and extensive comparison across those criteria. Nonetheless, my personal thought is that the field of model selection should be encouraged to astronomers to prevent fallacies of blindly fitting models which might be irrelevant to the information that the data set contains. Physics tells a correct model but data do the same.

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[ArXiv] Data-Driven Goodness-of-Fit Tests, Aug. 1, 2007 http://hea-www.harvard.edu/AstroStat/slog/2007/arxiv-data-driven-goodness-of-fit-tests/ http://hea-www.harvard.edu/AstroStat/slog/2007/arxiv-data-driven-goodness-of-fit-tests/#comments Fri, 17 Aug 2007 23:37:51 +0000 hlee http://hea-www.harvard.edu/AstroStat/slog/2007/arxiv-data-driven-goodness-of-fit-tests-aug-1-2007/ From arxiv/math.st:0708.0169v1
Data-Driven Goodness-of-Fit Tests by L. Mikhail

Goodness-of-Fit tests have been essential in astronomy to validate the chosen physical model to observed data whereas the limits of these tests have not been taken into consideration carefully when observed data were put into the model for estimating the model parameters. Therefore, I thought this paper would be helpful to have a thought on the different point of views between the astronomers’ practice of goodness-of-fit tests and the statisticians’ constructing tests. (Warning: the paper is abstract and theoretical.)

This paper began with presenting two approaches to constructing test statistics: 1. some measure of distance between the theoretical and empirical distributions like the Cramer-von Mises and the Komogorov-Smirnov statistics and 2. score test statistics, constructed in a way that the tests is asymptotically normal. As the second approach is preferred, the author confined his study to generalize the theory of score tests. The notion of the Neyman type (NT) test was introduced with very minimal assumptions to shape the statistics.

The author discussed the statistical inverse problems or the deconvolution problems of physics, seismology, optics, and imaging where noisy signals and measurements occur. These inverse problems induce the Neyman’s type statistics under appropriate regularity assumptions.

Other type of NT tests in terms of score functions and their consistency was presented in an abstract fashion.

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