This dataset presented results from psychophysics and modeling that supports the use of image statistics heuristics in the judgement of metallicity. To investigate visual features associated with the interpretation of metallic objects, five practiced participants (aged 23 to 28 years old) with normal color vision and normal or corrected-to-normal visual acuity were recruited to perform a conjoint-measurement task.

Maximum likelihood difference scaling (MLDS) trials: In each trial, participants viewed two pairs of computer-generated objects (stimuli) with a randomly deformed and rendered surface coating and were tasked to judge the relative differences between pairs and within pairs. 310 trials were completed with non-overlapping stimuli presentations.

Maximum likelihood conjoint measurement (MLCM) trials: In each trial, participants viewed a pair of stimuli and were asked to select the object that appeared “more likely to be made of metal”. Objects varied in features, dimension, and rotational angle. Participants were shown 325 pairs in a random order four times for a total of 1,300 trials.