Table 2. Model-specific parameters associated with each of the 14 models.

All models have an equivalent set of general parameters that describe how the primary decision is generated. However, the models differ in their assumptions about how confidence is generated, thus requiring a unique set of parameters to describe confidence decisions. The parameters indicated in bold text are dependent on the stimulus contrast/coherence levels (i.e., there is a separate free parameter for each contrast/coherence). Therefore, for Experiments 2/3, which feature three/eight difficulty levels, each of these parameters increase the total number of free parameters by three/eight. The WEV model was not fit to Experiment 1 because in the presence of a single difficulty level, the model becomes equivalent to the Gauss model.

Model	Additional parameters	Total # of parameters
		Expt 1	Expt 2	Expt 3
SDT	None	8	14	15
Gauss	${\sigma }_{\mathit{meta}}$ (meta noise)	9	15	16
$\mathrm{L}\mathrm{o}\mathrm{g}\mathrm{N}$	${\sigma }_{\mathit{meta}}$ (meta noise)	9	15	16
Decay	${\sigma }_{\mathit{meta}}$ (meta noise), ${\mathit{\rho }}_{\mathit{decay}}$ (proportion of sensory signal available for confidence)	10	18	24
Post-dec	${\delta }_{\mathit{post}}$ (post-decisional signal)	9	15	16
2DSD	$\tau$ (post-decisional signal)	9	15	16
PE	None	8	14	15
PE-Flex	${\mathit{w}}_{\mathit{pe}}$ (weight given to positive evidence)	9	17	23
WEV	$w_{vis}$ (weight given to stimulus visibility), ${\sigma }_{\mathit{meta}}$ (meta noise)	--	16	17
$\mathrm{B}\mathrm{C}\mathrm{H}$	None	--	14	15
CASANDRE	${\sigma }_{\mathit{meta}}$ (meta uncertainty)	9	15	16
DC	${\mathit{w}}_{\mathit{unconscious}}$ (proportion of the available signal accessed by the unconscious channel)	9	17	23
SDRM	${\sigma }_{dec}$ (noise in decision criterion), ${\sigma }_{\mathit{conf}}$ (noise in confidence criteria), $\rho$ (correlation between evidence samples for primary choice and confidence)	11	17	18
SOC	${\sigma }_{\mathit{conf}}$ (noise in confidence criteria), $\rho$ (correlation between evidence samples for primary choice and confidence)	10	16	17