Inverse Nth power detection law for Washburn’s lateral range curve

A detection law (the conditional detection rate) which corresponds to the model of Washburn’s lateral range curve is presented in this paper. The detection law dealt with here is a general one which includes the inverse cube law and the definite range law. The lateral range curve and the sweep width of this law are derived explicitly. Two methods for estimating the parameters of the law are presented and a set of actual data is analyzed. Applying the model, the forestalling detection problem is investigated in a search-and-search situation. Taking account of the forestalling detection by the target, the generalized formulas of the lateral range curve and the sweep width are derived.