Neither Ideal behaviour nor Bounded Rationality Account for Human Visual Search Performance

Human saccadic behaviour has been shown to be consistent with both optimal strategies (Najemnik & Geisler, 2008, JoV) and stochastic selection (Clarke, Green, Chantler & Hunt, 2016, JoV) in visual search. However, much of the evidence for these claims comes from experiments using uniform stimuli. In the split-­‐half search array shown below, the target is visible in the periphery if it is on the right half, but not if it is on the left (verified in a pilot study).