This article describes the too little/too much (TLTM) scale as an innovation in rating scale methodology that may facilitate research on the too-much-of-a-good-thing effect. Two studies demonstrate how this scale can improve the ability to detect curvilinear relationships in leadership research. In Study 1, leaders were rated twice on a set of leader behaviors: once using a traditional 5-point Likert scale and once using the TLTM scale, which ranged between –4 (much too little), 0 (the right amount), and þ4(much too much). Only linear effects were observed for the Likert ratings, while the TLTM ratings demonstrated curvilinear, inverted U-shaped relationships with performance. Segmented regressions indicated that Likert ratings provided variance associated with the too little range of the TLTM scale but not in the too much range. Further, the TLTM ratings added incremental
validity over Likert ratings, which was entirely due to variance from the too much range. Study 2 replicated these findings using a more fine-grained, 9-point Likert scale, ruling out differences in scale coarseness as an explanation for why the TLTM scale was better at detecting curvilinear effects.
Vergauwe, J., Wille, B., Hofmans, J., Kaiser, R. B., & De Fruyt, F. (2017). The "too little/too much" scale: A new rating format for detecting curvilinear effects. Organizational Research Methods, 20, 518-544.
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