Quantitative Scales, Curvilinear Relationships, and Transformations
In Chapter 6 we continue our treatment of quantitative scales; that is, scales that can take on a continuous range of values. We include ordinal, interval, and ratio scales (Section 1.3.3), and note that they share the minimum property that the scale numbers assigned to the objects order the objects with regard to the measured attribute. Ordinal (rank-order) scales have only this property, interval scales add the property of equal units (intervals), and ratio scales have both equal intervals and equal ratios, hence a true scale zero. Despite these differences in the amount of information they yield, we find it convenient to treat them together. To this point ...