RE: DV simulation problem

From: Sriram Krishnaswam Subject: RE: [NMusers] DV simulation problem Date: Sat, 7 Jun 2003 16:00:18 -0400 Hi, I generally use DV but in order to avoid simulation of practically impossible values (e.g negative concentration or >100% effect if simulated on a % scale), I use things like CALL SIMETA(ETA), CALL SIMEPS(EPS), DOWHILE LOOPS, Log transformation to avoid those impossible numbers. To me, it doesnt make sense to simply ignore the estimated residual variability when it comes to simulation. Among other unknown things, the res variance also contains measurement error, which is not going to go away just because you are simulating. Sometimes, if the residual variance is large, I try to do the abbreviated predictive check playing with differnt residual variance estimates and select one that "sufficiently" explains the observed data and then use it for other simulations. Would be very interested to hear opinions on this topic. Sriram Aventis, NJ