Objects do not predict fixations better than early saliency: A re-analysis of Einhauser et al.'s data

Einhäuser, Spain, and Perona (2008) explored an alternative hypothesis to saliency maps (i.e., spatial image outliers) and claimed that "objects predict fixations better than early saliency." To test their hypothesis, they measured eye movements of human observers while they inspected 93 photographs of common natural scenes (Uncommon Places dataset by Shore, Tillman, & Schmidt-Wulen 2004; Supplement Figure S4). Subjects were asked to observe an image and, immediately afterwards, to name objects they saw (remembered). Einhäuser et al. showed that a map made of manually drawn object regions, each object weighted by its recall frequency, predicts fixations in individual images better than early saliency. Due to important implications of this hypothesis, we investigate it further. The core of our analysis is explained here. Please refer to the Supplement for details.