The Emotion predictors use the observed facial expressions as input to calculate the likelihood of an emotion. Our Facial expression to emotion mapping builds on EMFACS mappings developed by Friesen & Ekman. A facial expression can have either a positive or a negative effect on the likelihood of an emotion. The following table shows the relationship between the facial expressions and the emotions predictors.
The Valence metric likelihood is calculated based on a set of observed facial expressions:
Engagement or expressiveness is a weighted sum of the following facial expressions: