Latent Variable

A latent variable is a variable that cannot be observed. The presence of latent variables, however, can be detected by their effects on variables that are observable. Most constructs in research are latent variables. Consider the psychological construct of anxiety, for example. Any single observable measure of anxiety, whether it is a self-report measure or an observational scale, cannot [Page 697]provide a pure measure of anxiety. Observable variables are affected by measurement error. Measurement error refers to the fact that scores often will not be identical if the same measure is given on two occasions or if equivalent forms of the measure are given on a single occasion. In addition, most observable variables are affected by method variance, with the results obtained using a method ...