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Methods for solving nonlinear equations used in evaluating emergency vehicle busy probabilities.

J Goldberg·F Szidarovszky
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Abstract

In this paper we present two iterative methods for solving a model to evaluate busy probabilities for Emergency Medical Service (EMS) vehicles. The model considers location dependent service times and is an alternative to the mean service calibration method; a procedure, used with the Hypercube Model, to accommodate travel times and location-dependent service times. We use monotonicity arguments to prove that one iterative method always converges to a solution. A large computational experiment suggests that both methods work satisfactorily in EMS systems with low ambulance busy probabilities and the method that always converges to a solution performs significantly better in EMS systems with high busy probabilities.

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AlgorithmsAmbulancesData CollectionEmergency Medical ServicesEvaluation Studies as TopicModels, StatisticalOperations ResearchProbabilityTime and Motion StudiesTravelUnited StatesWorkloadJournal Article

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J Goldberg, F Szidarovszky. Methods for solving nonlinear equations used in evaluating emergency vehicle busy probabilities.. https://doi.org/10.1287/opre.39.6.903

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