Since I am speaking at the Sentiment Analysis Symposium next week, I have had sentiment analysis on my mind, as you might imagine. What I find interesting is that, like so many other areas of natural language processing technology, it tends to have its own little niche of practitioners who are completely shut off from the other communities under the NLP umbrella. Very few who associate themselves with it have given much thought about the interaction of SA with information retrieval, machine translation or even document classification of which it is a proper part. The latter is especially surprising to me, since considering the semantic nature of the three (aha – or should there be two??) “traditional” sentiment classes – positive, negative and neutral –  raises  some important issues in the general semantics of  “opposition”. Lets start with the paradox of having more than two sentiment classes. The effect of that idea is to move sentiment analysis out of the semantic “bucket” of polarity altogether. Is that something that makes sense for usability and information quality? Does it open the door to making sentiment gradable in general? What would that mean? One thing it would mean is that any hope of alignment with human judgments – already shaky –  would be gone. It would also negatively impact usability by virtue of the weak semantic substance in the (theoretically infinite) number of sentiment classes. Each vendor of the technology could have a different proprietary scale making product comparisons impossible as an added distraction.

OK well maybe I’m getting a bit extreme……and we haven’t seen sentiment scales above three coming out in products.  But on the other hand is dividing the world of thought up by applying binary sentiment over popular opinion a reasonable classification goal as an alternative? Or is that too limiting? I actually believe that opening sentiment analysis up to explore the greater world of semantic “opposites” is the way to push the technology into a future of greater usability and profit. I suppose we’ll see what people think when I float that idea at my talk……..