How continuous is continuous enough? Comparing the reliability of continuous and discrete scales
摘要
Designing a reliable rating scale with an appropriate number of options remains a central issue in social science measurement. Prior studies have reported inconsistent findings, with some suggesting that reliability is maximized at moderate response granularity and others indicating that finer granularity yields higher precision. These inconsistencies may partly reflect methodological differences, particularly the use of classical test theory or the discretization of continuous responses, both of which may underestimate the reliability of continuous scales. To address these issues, the present study reconceptualized discrete and continuous scales as points along a unified granularity continuum and examined reliability using the continuous rating scale model (CoRSM). Utilizing the CoRSA analytical framework (Chou et al.,