Define/cite Otsuka-Chiai similarity

[Jbollenbacher]

One of the NLP options is a "Otsuka-Chiai" similarity between documents. What is this similarity? Is it the Ochiai coefficient (defined here) of the bags of words? I tried to find a reference to it in the NLP plugin code but I cant seem to find it.

Thanks

[spindensity]

I think Otsuka–Chiai is simply a mistake, it should be Otsuka–Ochiai similarity, that is, cosine similarity.