Correlation-induction techniques for estimating quantiles in simulation experiments

To estimate selected quantiles of the response of a finite-horizon simulation, we develop statistical methods based on correlation-induction techniques for variance reduction, with emphasis on antithetic variates and Latin hypercube sampling. The proposed multiple-sample quantile estimator is the average of negatively correlated quantile estimators computed from disjoint samples of the response, where negative correlation is induced between corresponding responses in different samples while mutual independence of responses is maintained within each sample. The proposed single-sample quantile estimator is computed from negatively correlated responses within one overall sample. We establish a central limit theorem for the single-sample estimator based on Latin hypercube sampling, showing that asymptotically this estimator is unbiased and has smaller variance than the comparable direct-simulation estimator based on independent replications. We also show that if the response is monotone in the simulation´s random-number inputs and if the response satisfies some other regularity conditions, then asymptotically the multiple-sample estimator is unbiased and has smaller mean square error than the direct-simulation estimator