In everyday usage, measurement occurs when an established yardstick verifies the height, weight or another feature of a physical object. How well you like a song, a painting, or the personality of a friend is also a measurement. In a dictionary sense, to measure is to discover the extent, dimensions, quantity, or capacity of something, especially by comparison with a standard. We measure casually in daily life, but in research the requirements are rigorous.
Measurement in research consists of assigning numbers to empirical events in compliance with a set of rules. This definition implies that measurement is a three part process:
- Selecting observable empirical events.
- Using numbers or symbols to represent aspects of the events, and
- Applying a mapping rule to connect the observation to the symbol.
As already noted, measurement is the assignment of numerals to objects or events according to some rules. A rule is a guide that directs you on how to go about assigning numerals. A numeral is a symbol of the form 1, 2, 3, or I, II, III…… A numeral has no quantitative meaning unless we give it such a meaning. It is simply a symbol of special kind. Numbers are used because they
facilitate communication of the measurement procedures and the results from researcher to researcher. In addition the use of numbers allows mathematical manipulations of the measurement data.
Measurement is a process of mapping aspects of a domain onto other aspects of a range according to some rule of correspondence. In measuring, we devise some form of scale in the range (in terms of set theory, range may refer to some set) and then transform or map the properties of objects from the domain (in terms of set theory, domain may refer to some other set) onto this scale.