Distance Estimates With "Filled" and "Unfilled" Space

The visual perception of lines on the road

“…Because the spaces between the lines were twice as long as the lines themselves, the spaces were underestimated by about a factor of two, as compared with the lines. This fits with previous work showing that unfilled space is generally seen as much smaller than filled space (Luria et al, 1967). Estimates of both the lines and the spaces in between the lines are consistent with a dramatic compression (from memory) of 3-D space in the plane parallel to an observer's line of sight.…”

“…To our knowledge, less work has been done considering whether an object or a filled area, such as a stake placed on the ground plane parallel to the line of sight of the observer, would also be subject to the large affine distortions that distances between stakes are. Previous work has shown that unfilled space is generally seen as much smaller than filled space (Luria, Kinney, & Weissman, 1967). In addition, would one get the same depth compression for the depth portion of an L-shape if the horizontal portion were removed?…”

Scaling apparent distance in natural indoor settings

“…There is also some evidence for a third alternative-that when Os are asked to judge target distances, the judgments are positively accelerated functions of physical distance. Kunnapas (1960) reported a series of experiments in which ratio estimations were made of pairs of indoor distances: apparent distance was a power function of DISCUSSION Our results confirm those of Kiinnapas (1960) and of Luria , Kinney, & Weissman (1967) in giving an exponent greater than 1.0 for indoor viewing. For two stimulus ranges, the mean exponents are 1.15 and 1.27, both significantly greater than 1.00, but not different from each other.…”

“…These distances were marked by irregular polygons, cut from black matte cardboard; there were 10 such physical distance with an exponent ranging from 1.2 to 1.5. Luria, Kinney, & Weissman (1967) had Os make distance judgments relative to a 2·ft standard distance; those judgments were power functions of target distance with exponents of 1.2 to 1.3. (Luria, Kinney, and Weissman did not fit power functions to their data.…”

Underestimation of Length by Subjects in Motion

“…The finding that the spaces are underestimated more than the segmented lines agrees with the well-known finding that unfilled spaces are underestimated more than filled spaces (e.g., Luria, 1967). It is also interesting to note thac having subjects look carefully at the stimuli apparently has no effect on the magnitude of the illusion at 60 mph, since subjects in Harte's (1975) previous study actually estimated about 7% better than subjects in the present srudy.…”