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Re: st: Weights
If I can weigh in on this, as someone who knows way too much about
file format internals...
SPSS (on disk) compresses each data element. It is extremely
efficient for typical survey data since each small signed integer
goes into one byte. Everything else goes into doubles. Strings are
stored in multiple fixed-length segments and not very efficiently at all.
If you run your data through Stat/Transfer into Stata format using
our default optimization, you will end with a file that will be the
same as one that has been compressed by Stata. This will occur
outside of Stata, so you will ultimately be able to use larger
datasets with a fixed amount of memory. You can also automatically
drop variables which are entirely missing or constant, which is
useful when you are creating subsets of rows for analysis.
Best,
Steve
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Steven Dubnoff [email protected]
Circle Systems We make your data instantly usable.
Download Stat/Transfer from http://www.stattransfer.com
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Seattle, WA 98154 Fax (206) 328-4788
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