Do capital letters, exclamation marks, and double negatives affect the sentiment score?
Capitalized letters are not considered by the engine for sentiment analysis, instead, the engine treats capitalized words as proper nouns, in which sentiment is not applied. Custom phrases entered into the sentiment dictionary should be lowercased so the engine considers the phrase as a common noun and extracts the sentiment appropriately.
Exclamation marks do affect the sentiment score and add multiplier to the sentiment. However, increasing the number of exclamation points does not continue to affect and intensify the sentiment because there is little sentiment difference between “Love it!” and “Love it!!!!!” and “Love it!!!”.
“An angry crowd storms Egyptian Government buildings.”
Receives an overall document sentiment score of -0.505, based on “storms” (-0.49) and “angry” (-0.52)
“An angry crowd storms Egyptian Government buildings!”
This receives an overall document sentiment score of -1.01, based on “storms” (-0.98) and “angry” (-1.04)
Additionally, when there is a double-negative phrase, such as "it was not, not terrible service" the engine will invert the score.