JMP 10 Modeling and Multivariate Methods

Chapter 22 

Scoring Tests Using Item Response Theory

Using the Item Analysis Platform

Item Response Theory (IRT) is a method of scoring tests. Although classical test theory methods have been widely used for a century, IRT provides a better and more scientifically based scoring procedure. Its advantages include:

• scoring tests at the item level, giving insight into the contributions of each item on the total test score

• producing scores of both the test takers and the test items on the same scale

• fitting nonlinear logistic curves, more representative of actual test performance than classical linear statistics.