NCJ Number
65784
Journal
OPERATIONS RESEARCH QUARTERLY Volume: 26 Issue: 2 Dated: (JANUARY 1976) Pages: 1-16
Date Published
1976
Length
16 pages
Annotation
A MODEL FOR DESIGNING POLICE PATROL BEATS IS PRESENTED WITH THE OBJECTIVE OF MINIMIZING RESPONSES TIMES OF PATROL UNITS.
Abstract
STUDIES SHOW THAT A REDUCTION IN THE TIME THAT PATROL UNITS TAKE TO ANSWER A CALL RESULTS IN A HIGHER PROBABILITY OF ARREST. DELAYS IN RESPONSE TIME INVOLVE TARDINESS IN REPORTING THE INCIDENT, IN THE COMMUNICATION CENTER'S DEVELOPMENT OF A REPORT, WAITING FOR A PATROL UNIT IF ALL UNITS ARE UNAVAILABLE, AND THE PATROL'S TRAVEL TIME TO THE SCENE. THIS RESEARCH CONCERNS THE LAST TWO ELEMENTS AND ASSUMES NO CONTROL OVER OTHER DELAYS. IN DEVELOPING THE EXPECTED RESPONSE TIME FOR A GIVEN CONFIGURATION OF POLICE BEATS, THE EFFECT OF DOWNTIME CALLS WAS DETERMINED AND CONSIDERATION WAS GIVEN TO TRAVEL TIME AND WAITING TIME. THE MODEL ASSUMED A POISSON DISTRIBUTION FOR ARRIVALS OF CALLS FOR SERVICES. MODELS WERE DEVELOPED FOR CALLS BEING DISPATCHED ACROSS BEAT BOUNDARIES AS WELL AS FOR INDEPENDENT BEATS. THE EFFECTS OF PRIORITY CALLS PREEMPTING NONPRIORITY CALLS ON RESPONSE TIME WERE ANALYZED. WHEN THE MODEL WAS TESTED ON THE AURORA POLICE DEPARTMENT (ILLINOIS), THE DATA WERE USED TO EQUALIZE THE WORKLOAD AND REDUCE RESPONSE TIME. BEATS WITH LARGE AREAS NEEDED A SLIGHTLY LESS THAN AVERAGE WORKLOAD TO ACCOUNT FOR LONGER TRAVEL TIMES. AN OPTIMAL SYSTEM OF EIGHT BEATS RESULTED IN A REDUCTION OF 12 PERCENT IN RESPONSE TIME COMPARED TO THE EXISTING CONFIGURATION. THE CONCLUSION THAT 1.02 LESS PATROL UNITS WERE NEEDED TRANSLATED INTO A YEARLY SAVINGS OF OVER $80,000. FIXED AND VARIABLE BEAT DESIGN STRATEGIES ARE DISCUSSED. REFERENCES ARE PROVIDED. (MJM)