I'm trying to fit 26046 observations with a linear model
y = mu + A + G + AG + CG + error
where A, G and C are factors of 22, 1185, and 10 levels,
respectively. Both lm() and glm() choke on this problem, giving
(after 35 minutes) the error message
Error in model.matrix.default(Terms, ..: Cannot create - data would have
length greater than 268435455 (.Machine$integer.max/sizeof(numeric))
Dumped
I had also received error messages about object.size limitations, but these
I could get past by setting options(object.size) to 1e10. Is there a
similarly easy fix for the present error? I observe that the base-16
logarithm of 268435455 is 7. Is this a problem of single-precision math?
My tools at hand are S-Plus 4.5 for Windows on a P166 with 64 Mb ram. I
also have R but don't know how to input the data (or do much of anything
yet) with it. I may also have access to an old SAS version on a
mainframe. Given these tools, is there a way I can do this regression?
I'll post a summary and my sincere thanks.
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John J. Thaden, Ph.D., Research Assistant Professor
Department of Geriatrics (501) 257-5583
U. Arkansas for Medical Sciences fax: (501) 257-4822
mailing & shipping address: jjthaden@flash.net
Central Arkansas Veterans Healthcare System
Research-LR151 (Room GB106)
4300 West 7th Street
Little Rock AR 72205 USA
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