Numeric values of psychological measures often have an arbitrary character before research has grounded their meanings, thereby providing what S. J. Messick (1995) called consequential validity (part of which H. Blanton and J. Jaccard now identify as metric meaningfulness). Some measures are predisposed by their design to acquire meanings easily,…

Many psychological tests have arbitrary metrics but are appropriate for testing psychological theories. Metric arbitrariness is a concern, however, when researchers wish to draw inferences about the true, absolute standing of a group or individual on the latent psychological dimension being measured. The authors illustrate this in the context of 2…