The AstroStat Slog » light curves 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] 3rd Week, Nov. 2007 http://hea-www.harvard.edu/AstroStat/slog/2007/arxiv-3rd-week-nov-2007/ http://hea-www.harvard.edu/AstroStat/slog/2007/arxiv-3rd-week-nov-2007/#comments Sun, 18 Nov 2007 06:50:10 +0000 hlee http://hea-www.harvard.edu/AstroStat/slog/2007/arxiv-3rd-week-nov-2007/ Greetings from Korea. I found that the menu on the right was almost invisible from my mother’s computer. The look seems OS and browser dependent. If you find any problems of viewing the slog, please notify me. Otherwise, please find a paper or two that drag your attention.

  • [astro-ph:0711.1353]
    How to use the SEDs produced by synthesis models (inside and outside the VO)? by M. Cervino and V. luridiana
  • [astro-ph:0711.1355]
    Synthesis models in a probabilistic framework: metrics of fitting by M. Cervino and V. luridiana
  • [astro-ph:0711.1633]
    Post Main Sequence Orbital Circularization of Binary Stars in the Large and Small Magellanic Clouds by L. Faccioli
  • [astro-ph:0711.1860]
    Cosmic Covariance and the Low Quadrupole Anisotropy of the Wilkinson Microwave Anisotropy Probe (WMAP) Data by L. Chiang, P. D. Naselsky and P. Coles
  • [astro-ph:0711.2068]
    Type Ia Supernovae are Good Standard Candles in the Near Infrared: Evidence from PAIRITEL by W. M. Wood-Vasey
  • [astro-ph:0711.2147]
    A Deconvolution technique for VHE Gamma-ray Astronomy, and its application to the morphological study of shell-type supernova remnants by G. Maurin, A. Djannati-Atai, and P. Espigat
  • [astro-ph:0711.2163]
    Predicting spectral features in galaxy spectra from broad-band photometry by F. B. Abdalla, et.al.
  • [astro-ph:0711.2222]
    X-ray afterglow light curves : toward standard candle ? by B. Gendre et.al.
  • [astro-ph:0711.2234]
    Consequences of statistical sense determination for WIMP directional detection by A, M. Green and B. Morgan
  • [astro-ph:0711.2477]
    Photometric Redshift Estimation on SDSS Data Using Random Forests S. Carliles et. al.
  • [astro-ph:0711.2480]
    Alignments of Voids in the Cosmic Web E. Platen, R. van de Weygaert and B. J.T. Jones
]]> http://hea-www.harvard.edu/AstroStat/slog/2007/arxiv-3rd-week-nov-2007/feed/ 0 Change Point Problem http://hea-www.harvard.edu/AstroStat/slog/2007/change-point-problem/ http://hea-www.harvard.edu/AstroStat/slog/2007/change-point-problem/#comments Wed, 08 Aug 2007 21:14:49 +0000 hlee http://hea-www.harvard.edu/AstroStat/slog/2007/change-point-problem/ X-ray summer school is on going. Numerous interesting topics were presented but not much about statistics (Only advice so far, “use implemented statistics in x-ray data reduction/analysis tools” and “it’s just a tool”). Nevertheless, I happened to talk two students extensively on their research topics, finding features from light curves. One was very empirical from comparing gamma ray burst trigger time to 24kHz observations and the other was statistical and algorithmic by using Bayesian Block. Sadly, I could not give them answers but the latter one dragged my attention.

Recently I went to JSM 2007 and tried to attend talks about (bayesian) change point problems, which frequently appears in time series models, often found in economics. With ARCH (autoregressive conditional heteroskedecity) or GARCH (generalized ARCH) and by adding a parameter indicates a change point, I thought bayesian modeling could handle astronomical light curves.

Developing algorithms based on statistical theories, writing algorithms down in a heuristics way, making the code public, and finding/processing proper datum examples from huge astronomical data archives should come simultaneously, and this multiple steps make proposing new statistics to astronomical society difficult. I’m glad to know that there are individuals who are devoting themselves to make these steps happened. Unfortunately, they are loners.

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