Results from two-pass experiments with model observers.

<p>In panels (a), (b), and (c) the filled circles show proportion correct and proportion of consistent responses for simulated internal-to-external noise ratios of 0, 1, and 2, respectively. Red symbols show results for the VPPM observer and green symbols show results for the MAP observer. For reference, blue lines in panels (a), (b) and (c) show the </p><p></p><p></p><p><mo stretchy="false">(</mo></p><p><mi>p</mi><mi>A</mi></p><mo>,</mo><p><mi>p</mi><mi>C</mi></p><mo stretchy="false">)</mo><p></p><p></p><p></p> contours for MAP observers with internal-to-external noise ratios of 0, 1, 2, 4, and the limit where internal noise dominates external noise (∞). Panel (d) replots data from the first three panels, showing the apparent internal-to-external noise ratio as a function of proportion correct. In panel (d), circles, diamonds, and squares show results for simulated internal-to-external noise ratios of 0, 1, and 2, respectively.<p>