ABSTRACT
School examinations might well be mistaken for interval scales and are often treated as if they were instances of the level of measurement. Measurement involves assigning numerals to objects and events according to rules. S. S. Stevens distinguishes levels of measurement or ways in which the process of assigning numerals to objects and events can be carried out. It is important to be able to recognise these distinctions because the interpretation of the results that are derived from any form of measurement and the kind of operation that can legitimately be performed on them is governed by the level of measurement involved. Nominal scales is the most primitive scale in the hierarchy and involves assigning numerals to objects and events simply as a convenient way of labelling and identifying them. Interval scales may be described as ordinal scales within which the intervals have been made equal. A thermometer provides an example of this kind of measurement.
