Allowing only Unique Survey Responses

[Alicia Abramson]

Has anyone ever put a survey on the Web and somehow controlled so that each
person who fills it out, can only do so once, so as not to skew the results?
I'm thinking the only way to do this would be to distribute "keys" in the
form of a unique password that once used becomes disabled...any other ideas?

If so how?  I'm interested in home grown solutions if any.

Thanks,

Alicia

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Alicia Abramson
Director, Library Information Systems
University Library
California State University, Sacramento
abramson at csus.edu
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