David M. Guion asks:
> Is it possible to delete all information that would reveal
> the identity of borrowers and still retain statistics not
> only on how many times an item circulates, but also how many
> different borrowers used it and what years (or semesters,
> etc.) it circulated?
It is possible, yes, but require some complicated manipulation.
Actually, it's not that difficult, since the technology has existed for
decades. All that is required is to translate the user number into some
other number or alphanumeric code in such a way that it is essentially
impossible to derive the original number from it, and in such a way that
the resulting codes never or almost never duplicate. Password
encryption software has done that since the early days of UNIX, and more
advanced algorithms exist now. Then you simply associate the encrypted
number with whatever user data you are recording for statistical
purposes.
Note that this is still not perfect. If a cracker got hold of the
statistics and found that encrypted user 987654 had book ABC out last
month, and also knows from independent sources that user John had ABC
out at that time, he can find all of John's circulation history by
searching for 987654. But I think that's as secure as you can get and
still associate unique users to circulation statistics. We can't
control what information other people can get on user library use from,
say, direct observation.
Steve McDonald
Tufts University
Received on Wed May 21 2008 - 14:02:56 EDT