Notes and Quotes

Hypothesis Testing

"Rejection of a true null hypothesis at the 0.05 level will occur only one in 20 times. The overwhelming majority of these false rejections will be based on test statistics close to the borderline value. If the null hypothesis is false, the inter-ocular traumatic test ["hit between the eyes"] will often suffice to reject it; calculation will serve only to verify clear intuition."
W. Edwards, Harold Lindman, Leonard J. Savage (1962) Bayesian Statistical Inference for Psychological Research. University of Michigan. Institute of Science and Technology.

The "inter-ocular traumatic test", IOTT, is attributed to Joseph Berkson, who also advocated logistic models.

Thurstone's Criteria for Freedom in Test Construction and Administration

1. Not required to have the same number of items at each difficulty level.

2. Permissible to omit items of any difficulty without affecting the subject's measure.

3. Item formats can include dichotomies and those that give a variable score, such as time in seconds or number of right answers or number of errors.

4. The range of item difficulty administered to the subject does not affect the subject's measure.

5. A measure can be determined for each subject, so that performances can be compared.

6. Arithmetical labor in determining subject measures is minimal. [With KeyMath, do it by eye!]

7. No imputation of responses to omitted items.

Paraphrased from L.L. Thurstone, The Scoring of Individual Performance. Journal of Educational Psychology, 1926, 17, 446-57.

Notes and Quotes. … Rasch Measurement Transactions, 1989, 3:2 pp.53

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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