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A. Biographies and . Thiongane, His main interests are estimating waiting time and modeling service time in call centers. He is currently working on the development of waiting time predictors in multi-skill call centers

P. L. Ecuyer, He holds the Canada Research Chair in Stochastic Simulation and Optimization and an Inria International Chair in Rennes, France. He is a member of the CIRRELT and GERAD research centers His main research interests are random number generation, quasi-Monte Carlo methods, efficiency improvement via variance reduction, sensitivity analysis and optimization of discrete-event stochastic systems, and discrete-event simulation in general. He has served as Editor-in- Chief for ACM Transactions on Modeling and Computer Simulation from 2010 to 2013, He is currently Associate Editor for ACM Transactions on Mathematical Software, Statistics and Computing, and International Transactions in Operational Research. More information can be found on his web page