Sentiment analysis – How is the overall customer sentiment score calculated?

Overall customer sentiment score

The customer sentiment score aims to capture the level of satisfaction experienced by the customer towards your company, products, or customer service. The customer sentiment score is computed by weighing each found sentiment event (positive or negative), with greater significance placed on the sentiment events that occurred towards the end of the interaction. In essence, the customer sentiment score answers the question, did the customer leave the interaction happy, or dissatisfied?

How is the overall customer sentiment score calculated?

The overall customer sentiment score is represented with a value that ranges from -100 to +100, with -100 being extremely dissatisfied and +100 being extremely satisfied.

The overall customers sentiment score is computed by weighing each found sentiment event (positive or negative) based on their relative location in the interaction with a greater weight towards the end of the interaction.

The relative location is calculated by taking the index of the customer’s phrase (in which the sentiment event takes place), and dividing that index by the total number of phrases on the customer side.

In the following examples, assume that each call has 42 total phrases, 20 of which are spoken by the customer.

Let’s assume the following events were detected by customer sentiment analysis:

Sentiment Event #	Sentiment Event	Event Location in the Interaction
1	Positive	0.50 (for example, 10th customer phrase in a 20 phrase call)
2	Positive	0.90 (for example, 18th customer phrase in a 20 phrase call)

As a result, the overall sentiment score would be f((+1 x 0.50) + (+1 x 0.90)) = f(1.40), where f is the function that normalized the customer sentiment score in the range -100 to +100. The function f is defined as Normalized Overall Sentiment Score = 100 x tanh(0.75 x Overall Sentiment Score), giving a Normalized Overall Sentiment Score of 78.

Another example:

Sentiment Event #	Sentiment Event	Event Location in the Interaction
1	Negative	0.10 (for example, 2nd customer phrase in a 20 phrase call)
2	Positive	0.40 (for example, 8^th customer phrase in a 20 phrase call)
3	Negative	0.85 (for example, 17^th customer phrase in a 20 phrase call)

As a result, the overall sentiment score would be f((-1 x 0.10) + (+1 x 0.40) + (-1 x 0.85)) = f(-0.55), where f is the function that normalized the customer sentiment score in the range -100 to +100. The function f is defined as Normalized Overall Sentiment Score = 100 x tanh(0.75 x Overall Sentiment Score), giving a Normalized Overall Sentiment Score of -39.

For more information, see Understand sentiment analysis.