Rogers Brian, Naumenko Olga
Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, UK,
Atten Percept Psychophys. 2015 Jan;77(1):249-57. doi: 10.3758/s13414-014-0767-3.
In the new moon illusion, the sun does not appear to be in a direction perpendicular to the boundary between the lit and dark sides of the moon, and aircraft jet trails appear to follow curved paths across the sky. In both cases, lines that are physically straight and parallel to the horizon appear to be curved. These observations prompted us to investigate the neglected question of how we are able to judge the straightness and parallelism of extended lines. To do this, we asked observers to judge the 2-D alignment of three artificial "stars" projected onto the dome of the Saint Petersburg Planetarium that varied in both their elevation and their separation in horizontal azimuth. The results showed that observers make substantial, systematic errors, biasing their judgments away from the veridical great-circle locations and toward equal-elevation settings. These findings further demonstrate that whenever information about the distance of extended lines or isolated points is insufficient, observers tend to assume equidistance, and as a consequence, their straightness judgments are biased toward the angular separation of straight and parallel lines.
在新月错觉中，太阳看起来并非处于与月球明暗面边界垂直的方向，并且飞机的喷气尾迹在空中似乎沿着弯曲的路径延伸。在这两种情况下，实际与地平线平行的直线看起来却是弯曲的。这些观察结果促使我们去研究一个被忽视的问题：我们是如何判断延长线的直线度和平行度的。为此，我们让观察者判断投射在圣彼得堡天文馆穹顶上的三个人造“星星”的二维排列情况，这些“星星”在仰角和水平方位角上的间距都有所不同。结果表明，观察者会出现大量的系统性误差，他们的判断偏离了真实的大圆位置，而偏向于等高设置。这些发现进一步证明，只要关于延长线或孤立点距离的信息不足，观察者往往会假定等距，因此，他们对直线度的判断会偏向于直线和平行线的角间距。
