Location, Location, Location: Position Effects in Choice Among Simultaneously Presented Options

Since its inception, psychology has studied position effects. But the position was a temporal one in sequential presentation, and the dependent variables related to memory and learning. This paper attempts to survey position effects when position is spatial (namely, position=location), all stimuli are presented simultaneously, and the dependent variable is choice. Unlike the ubiquitous "serial position curve", position effects in simultaneous choice are not consistent. A middle bias (advantage to being away from the edges) is the most common, but advantages to being first, last, or both, have also been recorded.