||Sensitivity Analyses of Parameters of a M(t)/G/infinity Stochastic Service System.
Patterson, R. L. ;
Ma, Z. Q. ;
||Michigan Univ., Ann Arbor. School of Natural Resources.;Environmental Research Lab.-Duluth, MN.
Stochastic processes ;
Regression analysis ;
Mathematical models ;
Data smoothing ;
Linear regression ;
Least squares method ;
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Parameter sensitivity analyses were conducted on a M(t)/G/infinity stochastic service system in which the number of constants in an approximating nonhomogenous Poisson process of inputs, the mean of a Weibull c.d.f. of service time, and the variance of the c.d.f. of service time were traded off in analyses of 24 cases for each of two fitting criteria: an L(1) metric implemented by a linear goal program, and an L(2) metric implemented by a multilinear least squares regression. The model goodness of fit and estimated total input to the system are both more sensitive to the mean service time than to its variance or to the number of constants in the approximating Poisson input. The fitting criteria give consistent results, the L(2) criterion gives slightly higher estimates of total input to the system over fixed period of time.