A methodology for emergency ambulance deployment
Fitzsimmons, J. A. (1973). A Methodology for Emergency Ambulance Deployment. [Journal Article]. Management Science, 19(6), 627-636.
An important feature of emergency ambulance systems is that the probability of any given unit being busy is dependent upon which of the other units are busy. An analytical model incorporating this feature is developed and found to be reliable in predicting the entire response time distribution for an actual operating system. A computer version of the model coupled with a pattern search routine constitutes the ambulance deployment methodology referred to as CALL (Computerized Ambulance Location Logic). This methodology may be used to find the deployment of ambulances that minimizes mean response time, as illustrated by an application for the City of Los Angeles. CALL was used to select from a possible set of 34 firehouses 14 for the location of emergency ambulances. Although the objective was the minimization of mean response time, the final deployment substantially reduced the probability of excessive response times as well. Another ancillary benefit from the use of CALL was a substantial smoothing of workload among the 14 ambulance crews.