You can compute emodiversity scores using the following formula derived from Shannon’s entropy:

 

 

 

 

 

 

where:

S = total number of emotions experienced (richness)

pi = proportion of S made up of the ith emotions

 

Specifically, in order to compute emodiversity, you should:

• Divide the number of times an individual experienced emotion #1 by the total number of times she experienced all types of emotions. This gave us p1.

• Multiply this proportion by its natural log (p1 * ln p1)

• Repeat this for each specific emotions assessed. 

• Sum all the (pi * ln pi) products and multiplied the total by -1.

 

High values are representative of more diverse emotional experiences. An individual experiencing only one type of emotion would have an emodiversity value of 0 because pi would equal 1 and be multiplied by ln pi, which would equal 0. If all the emotions of the list were evenly experienced then emodiversity would be maximal. So the emodiversity value captures in a single index not only the number of emotions an individual experience (richness) but also the relative abundance of the different emotions that makes a person’s emotional experience (evenness).