Word2Vec : Interpretation of Subtraction or addition of vectors I am curious, what does subtracting vectors, as in [man – woman] do in regards to Google's word2vec calculation of analogy ? Is this a measure of how different the two vectors are? So is
man – woman (approx.)= king – queen
saying the difference between man and woman is (approximately) the same as the difference between king and queen?
 A: Yes, that's my understanding of their interpretation; that's the reasoning behind why you'd expect (as observed) that [man] - [woman] + [king] ≈ [queen], or [Paris] - [France] + [China] ≈ [Beijing].
The idea is perhaps that vectors are approximately sums of their semantic components, so that [king] includes a "male" component as well as "ruler", "person", and whatever else, and [queen] has basically the same set of components except it has "female" instead of "male". [man] - [woman] would then end up at ["male"] - ["female"], so adding it to [king] would just swap the "male" concept for "female".
I kind of doubt there's a more complete understanding of it than that, though I'm not familiar with all of the literature on the subject and someone may have studied it in more detail.
A: Actually there has been some recent theoretical advances in understanding how the addition/subtraction of vectors works. See here: 
http://andyljones.tumblr.com/post/111299309808/why-word2vec-works
http://arxiv.org/abs/1502.03520
I would give a summary here - but I don't think I could do any better than Andy in his blog!
