Statistical Significance vs. Substantive Boundaries

"The major scientific disadvantage of [significance testing and confidence intervals] is that their significance is merely an inference derived from principles of mathematical probability, not an evaluation of substantive importance for the big or small magnitude of the observed distinction. ... They offer no guidance for the basic quantitative scientific appraisals that depend on purely descriptive rather than inferential boundaries. ... The latter evaluation has not received adequate attention during the emphasis on probabilistic decisions; and careful principles have not been developed either for the substantive reasoning, or for setting appropriate boundaries, for big or small. After a century of significance inferred exclusively from probabilities, a basic scientific challenge is to develop methods for deciding what is substantively impressive or trivial."

Feinstein, A. R. (1998). P-values and confidence intervals: Two sides of the same unsatisfactory coin. Journal of Clinical Epidemiology, 51(4), 355-60.

Courtesy of William P. Fisher

Psychological Measurement Impossible!

"Measurement can belong, therefore, only to that which is objective and spacial, and the psycho-physical quanta must stand for the physiological elements of our reactions, expressed in personal equations."

George Herbert Mead. "The Problem of Psychological Measurement", Proc. of the American Psychological Association, New York: MacMillan & Co. (1894): 22-23.

Science ...

Science consists of two general areas: there is the act of measurement, which is the empirical side of science, and there is the development of mechanisms, which is its theoretical side.

Dr. Dean Radin on "Closer to Truth", PBS, 2000

RMT 20:3 Miscellaneous Material, … Rasch Measurement Transactions, 2006, 20:3

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

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