title: The importance of search strategy for finding targets in open terrain.
abstract: A number of real-world search tasks (i.e. police search, detection of improvised explosive devices (IEDs)) require searchers to search exhaustively across open ground. In the present study, we simulated this problem by asking individuals (Experiments 1a and 1b) and dyads (Experiment 2) to search for coin targets pseudo-randomly located in a bounded area of open grassland terrain. In Experiment 1a, accuracy, search time, and the route used to search an area were measured. Participants tended to use an 'S'-shaped pattern with a common width of search lane. Increased accuracy was associated with slower, but also variable, search speed, though only when participants moved along the length (as opposed to across the width) of the search area. Experiment 1b varied the number of targets available within the bounded search area and in doing so varied target prevalence and density. The results confirmed that the route taken in Experiment 1a generalizes across variations in target prevalence/density. In Experiment 2, accuracy, search time, and the search strategy used by dyads was measured. While dyads were more accurate than individuals, dyads that opted to conduct two independent searches were more accurate than those who opted to split the search space. The implications of these results for individuals and dyads when searching for targets in open space are discussed.
authors.affiliation: University of Southampton, School of Psychology, Highfield, Southampton, Hampshire SO17 1BJ UK.
authors.forename: Charlotte A
authors.initials: CA
authors.lastname: Riggs
authors.affiliation: University of Southampton, School of Psychology, Highfield, Southampton, Hampshire SO17 1BJ UK.
authors.forename: Katherine
authors.initials: K
authors.lastname: Cornes
authors.affiliation: University of Southampton, School of Psychology, Highfield, Southampton, Hampshire SO17 1BJ UK.
authors.forename: Hayward J
authors.initials: HJ
authors.lastname: Godwin
authors.affiliation: University of Southampton, School of Psychology, Highfield, Southampton, Hampshire SO17 1BJ UK.
authors.forename: Simon P
authors.initials: SP
authors.lastname: Liversedge
authors.affiliation: University of Kent, School of Engineering and Digital Arts, Canterbury, Kent CT2 7NT UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Guest
authors.affiliation: University of Southampton, School of Psychology, Highfield, Southampton, Hampshire SO17 1BJ UK.
authors.forename: Nick
authors.initials: N
authors.lastname: Donnelly
keywords: Foraging; Large-scale search; Multiple targets; Paired searching; Search strategy; Visual search