Sentiments Analysis Vs emotion Analysis

Question

What is difference between sentiments (positive and negative) and emotions in text mining (NLP)? For example Anger is negative emotion as well as negative sentiment both seems the same. Vijay Nadadur, Creator of SentiRank, an algorithm which ranks sentiment in a text, Suggest Bio Sentiments can be expressed mostly in binary format (+ve & -ve) in a simplistic way. To add further, you may varying degrees of +ve and -ve sentiments, and perhaps neutral. However, emotions have multi-dimensions. Anger for sure is -ve sentiment, and so is sadness, but they aren't really the same.

To talk more specifically about text mining (NLP based), it's much simpler to do sentiment analysis but very hard to carry out emotional analysis. The next level of sentiment analysis is the field of intent analysis where few researchers have been working on mining out intent from the chunk of text, which seems of very high business value.

Answer 1

One could view emotion to be a finer-granularity sentiment. As you mention in the question itself, 'anger' and 'sadness' are both negative sentiments, but clearly, they are different emotions. Emotion analysis can thus be done as an additional layer on top of the (relatively) simple sentiment classification.

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| Sentiment Polarity | 10 Emotion Classes | Emotion word examples             |
|-----------------------------------------------------------------------------|
|                    |    Happiness       | happy, joyful, glad               |
|      Positive      |    Pleasantness    | pleasant, enjoy, nice             |
|                    |    Relief          | relief, comfort, solace           |
|-----------------------------------------------------------------------------|
|                    |    Fear            | scare, fear, frightening          |
|                    |    Sadness         | sad, grief, mourn                 |
|                    |    Disappointment  | bummer, regret, dejected          |
|      Negative      |    Unpleasantness  | dislike, yuck, irksome            |
|                    |    Loneliness      | lonely, withdrawn                 |
|                    |    Anxiety         | anxiety, worry, distress          |
|                    |    Anger           | anger, furious, antagonize        |
===============================================================================

Note that while sentiment classification can be binary, ternary or a graded system (of how +ve or -ve a sentiment is), emotion classification is much more open to interpretation. For example, one could add love as a positive emotion and hatred as a negative emotion. Keep in mind, however, that as we increase the number of classes, building an accurate classifier becomes more and more difficult. You may have to then start thinking of soft clustering approaches because the boundary between two emotions may not be clear (not just AI, it's sometimes not clear even to humans!).