An excellent session of the London Text Analytics Group (March 14) contrasted two approaches to sentiment analysis: one proudly (and publicly) ditches grammar, while the other uses grammar to disambiguate content. Both approaches made ambitious claims for their software; which is the best approach?
Stephen Pulman of TheySay, a start up from the University of Oxford, had the more traditional approach. He pointed out that taking individual words by themselves can lead to great confusion. Just assessing whether something is positive or negative is not so simple: “Bacteria” is negative, and “kill” is negative, but “kills bacteria” is positive. More complex still, the phrase “never fails to kill bacteria” is highly positive. A bag-of-words approach is unlikely to pick up all these distinctions.