“…Beyond the reported motion structure, we asked if our participants’ subjective confidence was dependent on the stimulus ambiguity, as measured by the Bayesian model. The relation between experimentally reported subjective confidence and theoretically derived Bayesian confidence has been studied for a variety of tasks (Drugowitsch, Moreno-Bote, and Pouget, 2014; Galvin et al, 2003; Hangya, Sanders, and Kepecs, 2016; Kepecs and Mainen, 2012; H.-H. Li and Ma, 2020; Mamassian, 2016; Pouget, Drugowitsch, and Kepecs, 2016; Sanders, Hangya, and Kepecs, 2016), and the literature is often equivocal about the exact nature of the relation. We analyzed the participants’ reported confidence as a function of the Bayesian predicted confidence, p ( S | X ), where the prior P ( S ) is given by the fitted biases b S for each participant, and the structure S is evaluated at the human choice (Pouget, Drugowitsch, and Kepecs, 2016).…”