Measuring equity sensitivity

Purpose – To examine the Equity Sensitivity Instrument (ESI) and the Equity Preference Questionnaire (EPQ) in a single study in order to see how the two measures are related, as well as how they relate to other variables, in an effort to identify which scale constitutes a better measure of the equity sensitivity construct. Design/methodology/approach – Using a self‐report questionnaire with two samples, 164 students and 186 non‐students, we analyzed the convergent and discriminant validity of the ESI and the EPQ with established measures of Machiavellianism and Positive Affect/Negative Affect. Additionally, the study examined the factor structures of the ESI and the EPQ. Findings – The summated ESI and EPQ scales showed little correlation with each other. Factor analysis of the scales revealed that the EPQ was multidimensional, while the ESI was unidimensional. Mixed findings among factor correlations precluded a definitive assessment of convergent or discriminant validity for the two scales. Many studies limit their investigation to a single population – either students or the general population – yet this study found significant differences in students' scores when compared to non‐students' scores. Research limitations/implications – This study uses a single self‐administered survey with two samples to examine equity sensitivity; as such, it suffers from the same potential for mono‐method bias as have previous studies on this topic. Differences between student and non‐student responses raise serious concerns; is the difference an artifact of flawed scales, is it indicative of a trait that is situational or that may evolve over time and experience, or is it the result of an anomalous sample? Additional research is needed to tease apart these issues. Originality/value – This study highlights the differences between two scales purported to measure the same construct. The multidimensionality of the EPQ together with the lack of substantial correlation with the ESI lead one to conclude that the EPQ, while originally proposed to remedy problems with the ESI, has serious weaknesses itself. There is a critical need for further research on how to best measure this important construct.