[rsmith49]

I would imagine that AWS Comprehend utilizes a lot of customer feedback when training its internal models. However, they do advertise Comprehend as a general purpose NLP service, so they may have taken steps to make the models generalize to the non-feedback domain. In any case, on our set of sentiment data for customer feedback, Comprehend is outperformed by Google’s NLP API and our own internal model.

As for Azure, we actually did not factor their service into our comparison. This is definitely something to consider in future blog posts.