Assessing the validity of the postmaterialism index

Inglehart's postmaterialism thesis describes an individual-level process of value change. Little attention has been devoted to validating rite respons es to his postmaterialist-materialist index. The aggregate-level distributi ons may appear to reflect a postmaterialist-materialist dimension, even if at the individual level res,responses on the questions making up the index are random. The logic of the survey questions used for the index defines a baseline against which the actual distribution of responses can be compared . Using such a standard, we find that individual responses are not constrai ned by an underlying value dimension, in the sense se that the observed pat terns of responses increasingly do not differ from what one would, expect b y chance. Furthermore, as one would expect for a random variable, index sco res are virtually unexplainable as a dependent variable, and they cannot be used to predict support for various political and social issues, said to f low from attitudes measured by the index.