3.16 Perturbation variables: oneway streets Consider a very large grid of equally spaced oneway streets, with the direction of travel alternating from street to adjacent parallel street. Assume that the positions of the response unit and the incident are independent and uniformly distributed over the grid. It is assumed that the response distance from the response unit to the incident is a shortest path that remains on the streets of the grid and obeys the oneway constraints. Use perturbation variables to demonstrate that the mean extra distance traveled to the incident, due to the oneway travel constraints, is two blocks.
