yum install gcc-c++
pip install -U scikit-learn
Suppose you have two sets, and
, and you would like to know how similar they are. First you might ask, how big is their intersection?
That’s nice, but isn’t comparable across different sizes of sets, so let’s normalize it by the union of the two sizes.
This is called the Jaccard Index, and is a common measure of set similarity. It has the nice property of being 0 when the sets are disjoint, and 1 when they are identical.
SimHash
a hash function usually hashes different values to totally different hash values
simhash is one where similiar items are hashed to similiar hash values