A Derandomized Sparse Johnson-Lindenstrauss Transform
نویسندگان
چکیده
Recent work of [Dasgupta-Kumar-Sarlós, STOC 2010] gave a sparse Johnson-Lindenstrauss transform and left as a main open question whether their construction could be efficiently derandomized. We answer their question affirmatively by giving an alternative proof of their result requiring only bounded independence hash functions. Furthermore, the sparsity bound obtained in our proof is improved. The main ingredient in our proof is a spectral moment bound for quadratic forms that was recently used in [Diakonikolas-Kane-Nelson, CoRR abs/0911.3389].
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ورودعنوان ژورنال:
- Electronic Colloquium on Computational Complexity (ECCC)
دوره 17 شماره
صفحات -
تاریخ انتشار 2010