There is a significant number of Sentiment Analysis services in the market. At least seven, according to our count, offer a free evaluation API demo. Maybe there are more. As a result, identifying the pros and cons of each one of them is a complex and time-consuming task.
As a first step, we have started the test with a relatively simple sentence:
"The food was not bad, but the service was rather bad".
This sentence contains two different opinions (one about the "food" , another one about the "service"), with different polarities (positive about "food"; negative about "service").
What is the result of the analysis for this sentence in the different API demos?
Some trends we have detected:
- Most APIs provide a general score/value for the sentence (or the document), not identifying the actual topics affected by sentiment, “food” and “service”.
- Most APIs identify the expression “not bad” as negative, rather than positive. Probably due to a problem with detection of negation.
- Most APIs don’t identify polarity modifiers or intensifiers like “rather” (in “rather bad”).
Check it for yourself!