Blackwell Reference Online

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Measurement involves assigning numbers to characteristics of objects or events in such a way that the numbers reflect reality. Essentially, there are four different types of measurement scales: nominal (or categorical), ordinal, interval, and ratio. As we move from categorical to ratio, so the arithmetic powers of the measures increase. The selection of the appropriate descriptive statistical measure ( see descriptive statistics ) and/or test statistic depends upon, among other things, the type(s) of scales used to measure the variables of interest. use numbers to categorize objects or events. Thus, for a variable called gender, the number 1 can be used as a label for males, the number 2 as the label for females. Again for a variable such as occupation, doctors can be labeled 1, teachers 2, students 3, market researchers 4, and so on. The numbers are being used as shorthand to identify categories, and the numbers are replaceable by fuller descriptions or labels at any time. There is no suggestion that males precede females just because in everyday arithmetic 1 comes before 2, or that one female is worth two males because 2 is twice 1, or that adding a doctor to a teacher gives a student just because 1 plus 2 equals 3. The well‐known rules of arithmetic do not apply to these numbers for obvious reasons. use numbers to rank items in order. As with nominal scales, cases are given ... log in or subscribe to read full text