Hi: I have a large data set that I'm testing and I'm finding that preplot.gam is taking a very long amount of time to compute (like, more than 20 minutes). My machine is 32-bit, Debian unstable, 4GB memory, dual Xeon 3GHz. While the data set is very large, the gam() procedure is able to compute the model without any trouble, in a minute or so. Is there any reason why preplot.gam would be so slow? I am not using "newdata" in the preplot.gam function, so I am assuming that the memory is not a problem. Or could it be? Is it normal for preplot.gam to take so long on large data sets? I have not had this experience with S-Plus, on a lower quality machine, same data. Thanks, Paul