Generalizing from single target search to multiple target search

This study was conducted to generalize from models of human performance in single target search to multiple target search. The specific issue was exhaustive search for the complete set of targets on a search field, extending the work of Chan and Chan from a two-target exhaustive search. Mathematical modelling was based on earlier derivations of search for the first of a set of targets. Model and simulation results showed three quite different relationships between mean search time and the number of targets remaining in a search field. The human search strategy for multiple targets was close to the systematic strategy for the first few targets and was close to the random strategy for the last few targets. Plotting mean search time for multiple targets against the number of targets remaining would be a useful and unique way to show human use of systematic search strategy.