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Allocating Police Officers on a Statewide Basis - A Mathematical Model for the Illinois State

NCJ Number
Date Published
30 pages
The mathematical model described provides a method of assigning Illinois State police to maximize their service while minimizing delays and lack of visible presence.
The basic model for allocation contains three components: overhead, called administrative support; response, termed calls for service; and patrol, called policing and patrolling. The model incorporates the following premises: (1) wherever possible, the variables used to allocate personnel are exogenous to the control of the agency; (2) these variables are weakly correlated (multicollinearity is reduced); (3) the number of officers available for allocation is less then the total available (the remaining officers provide administrative support and are assigned by executive decision); (4) the amount of personnel to be assigned to a specific philosophy, e.g., answer calls for service, is not limited except by the total number of personnel available for allocation; and (5) the same techniques used for allocation can also be used for projecting needs. The model has been transferred to an IBM 360 and has been in use for more than 1 year. Upgrading from the original model has produced refinements in the allocations and a better balance between urban and rural patrol. The model has been used to evaluate the effect of several philosophies related to changes in strength for all districts. Its use has helped support a decision to put greater emphasis on rural patrol and to use more patrol on State highways compared to interstate highways. More recently, the model has been used to determine to what extent service would be curtailed by reductions in personnel. The next step is to use the premises of the model to make allocations of detectives. The mathematical formulae for the model are appended, and 12 notes and 23 references are provided.