Just About Right Scales
Ennis, D. M. (2003). IFPress, 6(3) 2-3.
When Goldilocks considered eating the bears’ porridge, she found one "too hot", one "too cold", and one "just right". It is not possible to know from this information whether Goldilocks perceived the porridges to be hot or cold in intensity; we just have relative information about the three porridges. Relative ratings such as just-about-right (JAR), ratings relative to a reference, and ratings of one product relative to another all share a common model. The purpose of this report is to discuss this model and explain how it can be used to interpret just-about-right ratings.
Figure 3: Scale means of five products relative to an ideal at zero.