Measurement, 6: 213–218, 2008
Copyright © Taylor & Francis Group, LLC
ISSN 1536-6367 print / 1536-6359 online
DOI: 10.1080/15366360802265987
HMES 1536-6367 1536-6359 Measurement, Vol. 6, No. 3, June 2008: pp. 1–10 Measurement
REJOINDER
Rejoinder: Continuing the Dialogue on
Invariant Measurement
REJOINDER Engelhard
George Engelhard, Jr.
Emory University
The major purpose of my focus article was to stimulate discussion regarding the
concept of invariant measurement. My intent was to provide a historical lens for
considering how our views of invariant measurement have evolved over time
through the work of three key measurement theorists: Guttman, Rasch, and
Mokken. The commentators have offered a variety of direct and indirect responses
to my focus article; they have raised few, if any, issues with which I disagree.
However, I would like to take this opportunity to continue the dialogue about
invariant measurement.
Key words: invariant measurement, Guttman, Rasch, Mokken
MILLSAP
Millsap (this issue) focuses his comments on the invariance of item calibrations
over different populations or subsets of examinees (sample-invariant calibration
of items). This is called measurement invariance, and includes research on differ-
ential item functioning, factorial invariance, and predictive invariance (Meredith,
2007). He stresses the idea that research workers must make a distinction
between invariance properties that are inherent in the structural aspects of the
model, and questions of whether or not invariance holds for a particular set of
Correspondence should be addressed to George Engelhard, Jr., Department of Educational Studies,
Emory University, 1784 North Decatur Road, Atlanta, GA 30322. E-mail: gengelh@emory.edu