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Adaptive density estimation for directional data using needlets

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 نشر من قبل Paolo Baldi
 تاريخ النشر 2008
  مجال البحث فيزياء
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This paper is concerned with density estimation of directional data on the sphere. We introduce a procedure based on thresholding on a new type of spherical wavelets called {it needlets}. We establish a minimax result and prove its optimality. We are motivated by astrophysical applications, in particular in connection with the analysis of ultra high energy cosmic rays.



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