Application of IRT, CFA, and CTT
Statistical approaches that are used in psychological testing and measurement continue to evolve. Many of the approaches that are still widely taught and used have a very long history, such as CTT, which is used to assess test item characteristics and improve the reliability and validity of a measure. In fact, much of what you have examined related to CFA, reliability, and validity previously in this course falls under the broad umbrella of CTT. Newer approaches, such as IRT, can be used to evaluate both items and respondents in the evaluation of a psychological measure.
In this assignment, you will determine which statistical approach (CTT, IRT, or CFA) you would use to evaluate the measure you developed earlier in the course.
To prepare for this assignment:
Review this week’s Learning Resources on CTT, IRT, and CFA.
Consider how IRT and CFA are similar to and different from classical test theory (CTT).
Pay particular attention to how the authors of the organizational commitment, positive and negative affect, and psychological empowerment articles used CTT and CFA approaches in their research. (Note: The authors did not use IRT in their research because it is a relatively new approach.)
Think about the kind of information obtained from all three approaches, and how that information may be helpful in evaluating a psychological measure.
Reflect on your own measure you developed earlier in the course. Identify which approach (CTT, IRT, or CFA) you would use to evaluate the measure and consider why.
Explain which approach (CTT, IRT, or CFA) you would use to evaluate the measure you have been developing. Justify your choice by noting why the approach would be best for your measure, and why the other approaches would not be the best approach.