This study used the corneal reflection technique to investigate causes of miscounting in a dot-counting inspection task. An analysis of subjects' eye movements showed that there were two causes of miscounting: making fewer eye movements than the number of objects to be counted and overlooking objects present in the boundary of the visual field. The type of miscounting depended on the number of dots to be counted and the time allotted. Search process trade-off curves were developed that show the proportion of the two processes in a trial. These curves were incorporated into a descriptive model of visual search.
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