# Are Call Center and Hospital Arrivals Well Modeled by Nonhomogeneous Poisson Processes?

@article{Kim2014AreCC, title={Are Call Center and Hospital Arrivals Well Modeled by Nonhomogeneous Poisson Processes?}, author={Song-Hee Kim and Ward Whitt}, journal={Manuf. Serv. Oper. Manag.}, year={2014}, volume={16}, pages={464-480} }

Service systems such as call centers and hospitals typically have strongly time-varying arrivals. A natural model for such an arrival process is a nonhomogeneous Poisson process (NHPP), but that should be tested by applying appropriate statistical tests to arrival data. Assuming that the NHPP has a rate that can be regarded as approximately piecewise-constant, a Kolmogorov–Smirnov (KS) statistical test of a Poisson process (PP) can be applied to test for a NHPP by combining data from separate…

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