Theory of Locality Sensitive Hashing - SNAP - Stanford University
Theory of Locality Sensitive Hashing - SNAP - Stanford University
Theory of Locality Sensitive Hashing - SNAP - Stanford University
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Pick a random vector v, which determines a<br />
hash function h v with two buckets<br />
h v(x) = +1 if v⋅x > 0; = -1 if v⋅x < 0<br />
LS-family H = set <strong>of</strong> all functions derived<br />
from any vector<br />
Claim: For points x and y,<br />
Pr[h(x) = h(y)] = 1 – d(x,y)/180<br />
1/19/2011 Jure Leskovec, <strong>Stanford</strong> C246: Mining Massive Datasets<br />
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