embedding for users and Whispers. u Learn a score function f(u,w) that gives scores of whispers given a user. Ex: u Define a rank function that ranks all whispers for all users *Jason Weston, Samy Bengio, and Nicolas Usunier. Large scale image annotation: learning to rank with joint word-image embeddings. Machine learning, 81(1):21–35, 2010. Whisper @ LA DS Meetup, 2015/03/23 f u,w ( )=U u ⋅W w rank u,w ( )= Ι f u,k ( )> f u,w ( ) { } k∈w,k≠w ∑