Thanks, that's helpful! And you can email me at <my HN username> at gmail.com.

I'm also curious if there are any ways to quantify, mathematically, the changes over time. There's the simple sum of the squares of the changes distance to get a sense of the "kinetic energy" of the system, but I'm wondering if there are some more clever analyses, especially something that can quantify localized changes versus global changes.

Edit: so are you running a separate word2vec thing for each year's dataset? If so, how to you map between them, because the orientation the word2vec mapping generates will be random, and I worry that trying to rotate the mappings to some common axis could obscure some of the data.