| Article ID: | iaor20105641 | 
| Volume: | 22 | 
| Issue: | 3 | 
| Start Page Number: | 482 | 
| End Page Number: | 492 | 
| Publication Date: | Jun 2010 | 
| Journal: | INFORMS Journal on Computing | 
| Authors: | Wan Hong, Nelson Barry L, Ankenman Bruce E | 
Controlled sequential bifurcation (CSB) is a factor-screening method for discrete-event simulations. It combines a multistage hypothesis testing procedure with the original sequential bifurcation procedure to control both the power for detecting important effects at each bifurcation step and the Type I error for each unimportant factor under heterogeneous variance conditions when a main-effects model applies. This paper improves the CSB procedure in two aspects. First, a new fully sequential hypothesis-testing procedure is introduced that greatly improves the efficiency of CSB. Moreover, this paper proposes CSB-X, a more general CSB procedure that has the same error control for screening main effects that CSB does, even when two-factor interactions are present. The performance of the new method is proven and compared with the original CSB procedure.