Randomized Algorithms 2017 A – Lecture 7 Dimension Reduction in l 2 ∗
نویسنده
چکیده
Using main lemma: Let L = G/ √ k, and recall we defined yi = Lxi. For every i < j, apply the lemma to xi − xj , then with probability at least 1− 2/n3, ∥yi − yj∥ = ∥L(xi − xj)∥ = ∥G(xi − xj)∥/ √ k ∈ (1± ε)∥xi − xj∥. ∗These notes summarize the material covered in class, usually skipping proofs, details, examples and so forth, and possibly adding some remarks, or pointers. The exercises are for self-practice and need not be handed in. In the interest of brevity, most references and credits were omitted.
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