Fig. Supplementary 1: Recovery analysis for curvature estimation.

We simulated 4 observers with different sensitivities, viewing 21 different sequences with varying perceptual curvature, and evaluated our ability to estimate the perceptual curvature from the same amount of data we use in our experiment. Simulated observers’ sensitivities span the range of human sensitivities, and perceptual curvatures vary from 0° to 180°. (a) Greedy, two-step estimation, that first estimates the most likely perceptual trajectory, and then measures its curvature, is plagued by substantial bias. (b) Our method, which estimates the most likely perceptual curvature given many plausible perceptual trajectories, is largely unbiased.