Research that may settle a long-standing dispute in psychometrics has earned an award for a researcher at The University of Cambridge Psychometrics Centre.
The 2011 Best Doctoral Dissertations Prize from the Psychometric Society was awarded to Dr Anna Brown for her thesis, entitled, How Item Response Theory can solve problems of ipsative data.
Her work was carried out at the University of Barcelona under the supervision of Professor Alberto Maydeu-Olivares and resolves a longstanding and sometimes acrimonious debate in the field of ipsative testing.
A psychometric test is ipsative if respondents are required to compare two or more options and pick the one that is most preferred. Ipsative tests are popular as, by forcing respondents to choose between equally desirable options, they are more difficult to fake.
However, as one problem is solved, another one created as the assumption of statistical independence of the two scales, on which so much psychometric rigor depends, is broken. Ipsative scores distort scale relationships and reliability estimates, and make interpretation of scores problematic.
Anna's research demonstrates how Item Response Theory (IRT) modelling may be applied to overcome these problems.