BRIEF October 4, 2018

Psychometrics

All impact evaluations depend on quantitative data that typically come from surveys, direct observations of children or service providers, and administrative data like scores from exams. To detect impacts of the interventions under evaluation, we need data that will appropriately measure changes in the outcomes we want the intervention to affect. How do we know we are using the right data and analyzing it appropriately? Enter psychometrics, which is the branch of psychology focused on the design, administration, and interpretation of quantitative assessments. Psychometric evaluations can tell you if you are using the right tools for your measurement goals.

 

Learning

Andrew Ho, professor of education at the Harvard Graduate School of Education, delivering a mini-course at the World Bank on psychometrics. He is a psychometrician whose research aims to improve the design, use, and interpretation of test scores in educational policy and practice. The following links offer a view into his course, along with corresponding materials.

Lectures

Mini-course presentation (Part 1), June 11, 2018, “Statistical and psychometric methods for measurement: Scale development and validation.”

Video, Slides

Mini-course presentation (Part 2), June 27, 2018, “Statistical and psychometric methods for measurement: G Theory, DIF, & Linking.”

Video, Slides

Studies referenced in the lectures

Jessen A, Ho AD, Corrales CE, Yueh B, Shin JJ. Improving Measurement Efficiency of the Inner EAR Scale with Item Response Theory. Otolaryngology–Head and Neck Surgery
2018, Vol. 158(6) 1093–1100.

Appendix
, Stata code

Duckworth AL, Quinn PD. Development and Validation of the Short Grit Scale (Grit–S). Journal of Personality Assessment, 91(2), 166–174, 2009.

Other code and data referenced in lectures