Getting Students Interested in Psychological Measurement by Experiencing the Barnum Effect

Abstract

Background: Fake psychological tests tend to be viewed as completely believable (Barnum effect), meaning psychometric properties cannot be judged subjectively. Experiencing this effect first-hand could help get students interested in the science of psychological assessment. Objective: In a blended learning perspective, we created materials to elicit a Barnum effect with a brief online fake test and tested the benefits of this procedure for student engagement. Method: Five cohorts of undergraduate psychology students (total N = 2,269) completed the fake test online prior to their first psychometrics course. We collected single-item ratings of perceived effectiveness for the test, willingness to use it, and course engagement (interest and enthusiasm for the course). We also retrieved grades. Results: Eighty-five percent of students rated the effectiveness of the fake test above the neutral point; 77% were willing to use it as future psychologists. Experiencing the effect was related to significantly increased interest and enthusiasm, and higher grades. Conclusion: Having students experience the Barnum effect for themselves is a useful and effortless approach to get them interested in psychometrics. Teaching Implications: Teachers of introductory courses related to psychological measurement should consider having all students experience the Barnum effect. All materials are provided.