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Extreme Value Statistics in SDSS. Enikő Regős (CERN, ELTE). Distribution of Maximal Luminosity of Galaxies. w Szalay, Rácz, Taghizadeh, Ozogany Non-parametric statistics Asymptotic distribution of extreme order statistics converges to Gumbel, Fréchet or Weibull
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Extreme Value Statistics in SDSS Enikő Regős (CERN, ELTE)
Distribution of Maximal Luminosity of Galaxies • w Szalay, Rácz, Taghizadeh, Ozogany • Non-parametric statistics • Asymptotic distribution of extreme order statistics converges to Gumbel, Fréchet or Weibull • Need large data bases: galaxy sample
Extreme Value Statistics & Galaxies • Selected from luminosities in a given direction and solid angle • Pixelized distribution of galaxy lum’s • Fischer-Tippett-Gumbel distribution corresponds to Press-Schechter parent distribution • EVS have large finite-size corrections
Data Bases : SDSS DR6 • Main Galaxy Sample blue, red, • Luminous Red Galaxies • Petrosian r band • Healpixes • Morphology-density relation » EVS separately
Model Data - Gumbel by finite-size corrections & variable sample size
Conclusions • Comparison of EVS luminosities w Fischer-Tippett-Gumbel (limit distribution for Press-Schechter) indicates good agreement • with uncertainties from finite size of samples and variable sample size (distribution)