Does familiarity breed contempt?

Student evaluation of faculty teaching performance is fast becoming a high-stakes game, but few are interested in measuring attributes influencing good teaching - most settle for some sort of statistical interpretation of counts.

Differential Item Functioning: small vs. large classes

The SFT (Student Feedback about Teaching) scheme at James Cook University in Australia is based on Rasch modelled estimates of responses to a Likert-type scale. In order to help to address a perennial question about how difficult it is to teach large classes, responses for classes smaller than N=30 were pooled, as were responses for classes larger than N=150 to generate the DIF plot above. While about half of the items located close to identically for both groups (with suitable allowance for measurement error), it was easier for students in small classes to report satisfaction with the `Interest' their teachers showed and the `Assessment Information' they provided. While teachers of large classes were reported as doing better at achieving the subject's `Aims', the largest DIF effect was for the easiest to endorse item: the teacher in the large lecture theater is much more readily seen as being an `Expert' in the field. (Disclaimer of personal interest; the author teaches classes of 450 first year teacher education students about developmental psychology.)

Trevor Bond

From: Trevor G. Bond, "Accountability in the Academy: Rasch measurement of student surveys", Survey Research in Education SIG, AERA 2002.

Does familiarity breed contempt? Bond TG. … 16:1 p.859

Does familiarity breed contempt? Bond TG. … Rasch Measurement Transactions, 2002, 16:1 p.859

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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