http://qiita.com/okappy/items/32a7ba7eddf8203c9fa1
http://qiita.com/shima_x/items/196e8d823412e45680e9

http://hibari1121.blog.fc2.com/blog-entry-53.html

http://satomacoto.blogspot.jp/2015/02/doc2vec.html
http://qiita.com/HirofumiYashima/items/f358228060f5d7a9b67e#_reference-a1f58b0039c7b4b5342b

https://rare-technologies.com/doc2vec-tutorial/