Preferred correlated colour temperature changes when the stimulus range differs

MWE for (journal doi) for more info or questions see doi or contact first or last author Abstract Preferences for correlated colour temperature (CCT) are often used to guide lighting design, yet the reliability of psychophysical methods to measure them remains uncertain. Central tendency bias, in particular, may systematically distort reported “preferred” CCT values, but its effect across different psychophysical methods has not been well established. This study examined two psychophysical approaches, paired comparisons (relative scaling) and semantic differential scales (absolute scaling), across three semi-overlapping CCT ranges. Twenty-four naive participants completed all experiments under controlled laboratory settings. Paired comparison data were analysed with a generalised linear model, and semantic differential data with non-parametric repeated-measures tests. The experiment was designed to determine (i) whether preference peaks shift when the tested CCT range changes, and (ii) whether absolute and relative scaling methods produce comparable preference functions.