Motion/Pursuit Ratio and Depth in 1D (Visual Depth Perception 17)
The relative error in using instead of the motion/pursuit law is . This Demonstration interactively computes the error.
Experimental evidence suggests that people underestimate relative depth for distractors beyond the fixate () and overestimate closeness (or for distractors nearer than the fixate. The motion/pursuit ratio has this relationship to the motion/pursuit depth formula, so it is possible that the ratio alone is a better estimate of the perceived depth.
The Demonstration "Motion/Pursuit Ratio and Depth in 2D (Visual Depth Perception 18)" (see Related Links) compares the motion/pursuit ratio and the motion pursuit law in two distractor dimensions.