2 ms·
This special case is a common recommendation situation, for a matrix X of (unit) user-vectors (whose entries are, eg., preferences for products/1)... then X^TX
by mjburgess 5y ago
This special case is a common recommendation situation, for a matrix X of (unit) user-vectors (whose entries are, eg., preferences for products/1)... then X^TX compares all users with all other users.