Test Scoring and Analysis Using SAS

Chapter 8: An Introduction to Item Response Theory - PROC IRT

Introduction

IRT basics

Looking at Some IRT Results

What We Aren’t Looking At!

Preparing the Data Set for PROC IRT

Running PROC IRT

Running Other Models

Classical Item Analysis on the 30-Item Physics Test

Conclusion

References

Introduction

IRT stands for Item Response Theory, an approach to analyzing test data and building tests that has been in development since the 1960s. It is sometimes referred to as modern test theory as opposed to classical test theory, which employs concepts like Cronbach’s coefficient alpha and item/test correlations. Although classical test theory is still widely used, especially in cases where the test is used only once and for situations where the number ...