EARLY STATISTICAL PROCESSING OF PERCEPTUAL INFORMATION: SELECTIVE ATTENTION TO THE MEAN AND VARIANCE OF LENGTHS OF LINES
Participants made speeded classifications of the mean (large, small) and the variance (large, small) of collections of physical lines. The selectivity of attention to each statistical moment was gauged by Garner effects. We found that the mean and the variance are integral statistical attributes: People are unable to perceive one without noticing the other. This mutual dependence of the two moments is inconsistent with standard statistical theory. These results also mandate a fresh look on the new wave of studies on representations of statistical properties, on the one hand, and on the classic psychophysical laws by Weber and by Hick, on the other hand.