MEASUREMENT SCALES

We consider the problem of measurement scales, which is an essential issue with regard every statistical analysis, in particular also in the analysis of Customer Satisfaction (CS) surveys.1 In Section 4.2 we present the problem of scale construction and the different types of scales, commonly used in CS surveys, that is the nominal, ordinal, interval and ratio scales. In Section 4.3 we consider the problem of obtaining an interval scale from an ordinal one; the resulting scale has a more informative characterization. In this context scaling methods are taken into account to obtain also a unifying scale for a set of homogeneous item in a questionnaire.