"A metric, once made meaningful, can be used to provide perspectives about such things as the magnitude of change that occurs on an underlying dimension as a function of an intervention. Evidence that an intervention causes movement along a scale that has nonarbitrary meaning can reveal the real-world consequences of this change."
"It can be difficult and time consuming to conduct the research needed to make a metric less arbitrary. Fortunately, the issue of metric arbitrariness is irrelevant for many research goals, so not all researchers must tackle this issue. ... However, there are applied situations in which researchers need to address the issue if they are going to fulfill their research goals. Tying metrics to meaningful, real-word events provides a viable means of making metrics less arbitrary, but there will always be some guesswork involved. No new methodology is going to expose psychological constructs to the naked eye. Best estimates of where people stand on psychological dimensions are always that, estimates. Nevertheless, awareness of this limitation is of value to the psychologist. A researcher who appreciates the gap between a psychological metric and a psychological reality knows to look past a person's score and search for something meaningful."
Blanton, H., and J. Jaccard. 2006. Arbitrary metrics in psychology. American Psychologist 61 (January):27-41.
Measuring Teacher Ability with the Rasch Model by Scaling a Series of Product and Performance Tasks. Judy R. Wilkerson and William Steve Lang
An Introduction to the Theory of Unidimensional Unfolding. Andrew Kyngdon
Estimating Person Locations from Partial Credit Data Containing Missing Responses. R. J. De Ayala
Validation of a Questionnaire Used to Assess Safety and Professionalism among Arborists. Steven G. Viger, Edward W. Wolfe, Hallie Dozier, and Krisanna Machtmes
How Accurate Are Lexile Text Measures? A. Jackson Stenner, Hall Burdick, Eleanor E. Sanford, and Donald S. Burdick
Rasch Analysis of the Structure of Health Risk Behavior in South African Adolescents. Elias Mpofu, Linda Caldwell, Edward Smith, Alan J. Fisher, Christine Mathews, Lisa Wagner, and Tania Vergnani
Understanding Rasch Measurement: Multicomponent Latent Trait Models for Complex Tasks. Susan E. Embretson and Xiangdong Yang
RMT 20:1 Miscellaneous Material, … Rasch Measurement Transactions, 2006, 20:1
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