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Efficient l_{alpha} Distance Approximation for High Dimensional Data Using alpha-Stable Projection

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 نشر من قبل Ioana Cosma
 تاريخ النشر 2008
  مجال البحث الاحصاء الرياضي
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In recent years, large high-dimensional data sets have become commonplace in a wide range of applications in science and commerce. Techniques for dimension reduction are of primary concern in statistical analysis. Projection methods play an important role. We investigate the use of projection algorithms that exploit properties of the alpha-stable distributions. We show that l_{alpha} distances and quasi-distances can be recovered from random projections with full statistical efficiency by L-estimation. The computational requirements of our algorithm are modest; after a once-and-for-all calculation to determine an array of length k, the algorithm runs in O(k) time for each distance, where k is the reduced dimension of the projection.


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