Standard Setting Methods

"Underlying the concept of achievement testing is the notion of a continuum of knowledge acquisition." Glaser, 1963

"The idea of a measure requires an idea of a variable on which the measure is located... Our intention is to show how calibrated items can be used to define a variable." Wright & Stone, Best Test Design, 1979

Practitioners of modern measurement have realized the hazards of using untransformed raw scores in every area except one - that of setting performance standards. The employment of antiquated models, such as Angoff (1971), seems to be more the rule than the exception.

Objective standard setting (Wright & Grosse, RMT 7:3 p. 315-6,1993) has demonstrated its psychometric effectiveness at providing testing bodies with reasonable ways to develop stable standards, which also produce acceptable examinee pass rates. The traditional models, like Angoff, have not produced useful results without a variety of "adjustments" which alter and corrupt whatever standard does emerge. The differences between the Objective and Angoff style approaches are more fundamental than pass rate stability, however. Indeed, the meaning and existence of the construct upon which the standard is based is considerably different. [Another attempt at objective standard setting is the Lewis, Mitzel, Green (1996) IRT-based Bookmark standard-setting procedure.]

Angoff attempts to quantify only one point on a construct by asking judge panels to define "minimal competence". This "quantification" is generated solely from predictions of examinee success and is expressed as a proportion of correct responses on the entire test (e.g. a raw score of 100 out of 150). Such simple, untransformed proportions are useless for the construction of meaning, however, because no variable is defined.

The Objective model asks judges to define required knowledge directly through item selection. Wright and Stone (1979) demonstrate that item calibrations define the variable and quantify the standard. The Figure illustrates a judge-defined standard from a recent objective standard setting conducted at the National Certification Corporation. The items are placed at their empirical logit difficulties. Inspection of their content discloses the stratification indicated. The judges then located the "Standard" at a defensible transition point between basic and advanced items. This Figure demonstrates how the Objective model allows for a clear and meaningful description of the standard. Such a description requires the adequate construction of a variable. The construct, itself, quantifies the qualitative understanding.

The vagaries of the Angoff method are replaced in the Objective approach with clear definitions, descriptions and quantifications. Whereas Angoff may begin with content, it ends up atomized into hundreds of contentless score fractions. Only an Objective approach retains the full richness of content understanding throughout the process, synthesizing it into a useful definition of the meaning of the standard.

------------------------------------------------
Item     Item         Item Descriptors
Logit    Map
------------------------------------------------
7.00     x
         x            Items in this range:
         x
         xxx          Advanced Physiology
         x            New Medical Advances
         xxx          Drug Dosage Calculations
6.0      xxxx         Psycho-Social Questions
         xxxxx
         xxxx
------------------------------------------------
         xxxxxxxxxx   STANDARD
         xxxxxxxxx
         xxxxxxx      Items in this range:
5.0      xxxxxxx
         xxxxxx       Gen Anatomy/Physiology
         xx           Intake/Evaluation
         xxxx         Routine Patient Care
         xxxx         Drug Usage
         x            Diagnostic Tools
4.0      x
------------------------------------------------

Angoff W.H. 1971. Scales, norms and equivalent scores. Chapter 15 in R.L. Thorndike, ed., Educational Measurement, 2 Ed. Washington DC: American Council on Education.

Glaser, R. 1963. Instructional technology and the measurement of learning. American Psychologist 18 519-521.

Lewis D.M., Mitzel, H. C., Green, D. R. (1996). Standard Setting: A Bookmark Approach. In D. R. Green (Chair), IRT-Based Standard-Setting Procedures Utilizing Behavioral Anchoring. Symposium presented at the 1996 Council of Chief State School Officers 1996 National Conference on Large Scale Assessment, Phoenix, AZ.


Standard setting methods. Stone GE. … Rasch Measurement Transactions, 1995, 9:3 p.452



Rasch Publications
Rasch Measurement Transactions (free, online) Rasch Measurement research papers (free, online) Probabilistic Models for Some Intelligence and Attainment Tests, Georg Rasch Applying the Rasch Model 3rd. Ed., Bond & Fox Best Test Design, Wright & Stone
Rating Scale Analysis, Wright & Masters Introduction to Rasch Measurement, E. Smith & R. Smith Introduction to Many-Facet Rasch Measurement, Thomas Eckes Invariant Measurement: Using Rasch Models in the Social, Behavioral, and Health Sciences, George Engelhard, Jr. Statistical Analyses for Language Testers, Rita Green
Rasch Models: Foundations, Recent Developments, and Applications, Fischer & Molenaar Journal of Applied Measurement Rasch models for measurement, David Andrich Constructing Measures, Mark Wilson Rasch Analysis in the Human Sciences, Boone, Stave, Yale
in Spanish: Análisis de Rasch para todos, Agustín Tristán Mediciones, Posicionamientos y Diagnósticos Competitivos, Juan Ramón Oreja Rodríguez

To be emailed about new material on www.rasch.org
please enter your email address here:

I want to Subscribe: & click below
I want to Unsubscribe: & click below

Please set your SPAM filter to accept emails from Rasch.org

www.rasch.org welcomes your comments:

Your email address (if you want us to reply):

 

ForumRasch Measurement Forum to discuss any Rasch-related topic

Go to Top of Page
Go to index of all Rasch Measurement Transactions
AERA members: Join the Rasch Measurement SIG and receive the printed version of RMT
Some back issues of RMT are available as bound volumes
Subscribe to Journal of Applied Measurement

Go to Institute for Objective Measurement Home Page. The Rasch Measurement SIG (AERA) thanks the Institute for Objective Measurement for inviting the publication of Rasch Measurement Transactions on the Institute's website, www.rasch.org.

Coming Rasch-related Events
July 30 - Nov., 2018Online Introduction to Classical and Rasch Measurement Theories (D.Andrich), University of Western Australia, Perth, Australia, http://www.education.uwa.edu.au/ppl/courses
Oct. 12 - Nov. 9, 2018, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Core Topics (E. Smith, Winsteps), www.statistics.com
Jan. 25 - Feb. 22, 2019, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Core Topics (E. Smith, Winsteps), www.statistics.com
Jan. 28, 2019 On-line course: Understanding Rasch Measurement Theory (ACER), https://www.acer.org/professional-learning/postgraduate/Rasch
April 4 - 8, 2019, Thur.-Mon. NCME annual meeting, Toronto, Canada.https://ncme.connectedcommunity.org/meetings/annual
April 5 - 9, 2019, Fri.-Tue. AERA annual meeting, Toronto, Canada.www.aera.net/Events-Meetings/Annual-Meeting
May 24 - June 21, 2019, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Core Topics (E. Smith, Winsteps), www.statistics.com
June 28 - July 26, 2019, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Further Topics (E. Smith, Winsteps), www.statistics.com
Aug. 9 - Sept. 6, 2019, Fri.-Fri. On-line workshop: Many-Facet Rasch Measurement (E. Smith, Facets), www.statistics.com
Oct. 11 - Nov. 8, 2019, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Core Topics (E. Smith, Winsteps), www.statistics.com
Jan. 24 - Feb. 21, 2020, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Core Topics (E. Smith, Winsteps), www.statistics.com
May 22 - June 19, 2020, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Core Topics (E. Smith, Winsteps), www.statistics.com
June 26 - July 24, 2020, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Further Topics (E. Smith, Winsteps), www.statistics.com
Aug. 7 - Sept. 4, 2020, Fri.-Fri. On-line workshop: Many-Facet Rasch Measurement (E. Smith, Facets), www.statistics.com
Oct. 9 - Nov. 6, 2020, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Core Topics (E. Smith, Winsteps), www.statistics.com
June 25 - July 23, 2021, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Further Topics (E. Smith, Winsteps), www.statistics.com

 

The URL of this page is www.rasch.org/rmt/rmt93m.htm

Website: www.rasch.org/rmt/contents.htm