The Tonality effect:
Definition: Impact on the average due to changes of tonality if no change in weights
Considering the assumption that the categories have kept the same weights, what are the impact(s) of the changes in tonality on the global average ?
Ex1: Imagine the following situation in a restaurant:
(IMPORTANT : To simplify here, 1 comment = 1 category)
For each category:
Tonality effect = Delta E-index (of the 2 periods) x Relative Weight N-1
The same effect can be calculated for the Satisfaction averaged scores, Recommendation averages, etc.