MetricsFlare Success Score Calculation
Success score calculation or otherwise, just a score calculation for a certain survey type we are using can be a matter of philosophical debate.
NPS has a pretty simple designed approach to calculating the score deriving from the responses to it. Percentage of detractors (those who rated your survey with anything from 0 to 6) deducted from the percentage of promoters (those who rated your survey with 9 or 10). The final result should be anywhere between -100 and 100. Anything above 30 is considered fine, above 50 good, and above 70 or 75 very good.
Now, when we want to understand the results from CSAT or CES surveys we need to be creative. As there is no standard or practice like with NPS there has to be a mechanism that is making sense mathematically as well as philosophically. The way we did it is that we have defined who are promoters and detractors on the 5-level CSAT scale or 7-level CES scale and then used the NPS logic for success score calculation. We are treating anything from very unsatisfied to Neutral as detractors; Satisfied and Very Satisfied as promoters for CSAT survey type.
Anything from Strongly Disagree to Neutral is considered a detractor; Agree and Strongly Agree are considered promoters for CES.
The mechanism we have implemented resides on the philosophy that the five-level scale (CSAT) has a smaller breakpoint between detractors and promoters. The neutral rates should be joined with detractors. The reasoning here is that chances are that neutral rates are statistically closer to becoming detractors than promoters.
We have decided to implement this mechanism to CSAT survey types due to its shorter scale. Also, we left the score calculation for CES and NPS on the three-level groups of detractors, neutrals, and promoters. Only CSAT shouldn’t separate neutrals from detractors.