Biometrics

[Kenneth Brody]

Fairlight wrote:
> 
> Only Kenneth Brody would say something like:
[...]
> > However, even the same finger, taken by the same scanner, will not
> > likely give identical data on more than one scan.  Every time you
> > scan the finger, you will probably get different biometric data.
> > (Unless you happen to place the finger with the exact same pressure
> > on the exact same place on the scanner, causing the scanner to give
> > an identical image.)
> 
> If it's not returning identical data, then what good is it?  If you get
> 'abc' one time and 'abg' the next, then how is it supposed to validate a
> thing?

And therein lies the science ("art"?) of biometrics.

>  If it's based on a range of probable matches, then suddenly you
> have a larger potential for overlapping false positive matches.  This
> is starting to sound less like science and more like a gimmick with
> each passing revelation.  Sounds like a more appropriate term would be
> bioguesstricks.

How do you think the FBI does things?  You don't think that in today's
world of computers, that they manually scan every fingerprint card for
a match, do you?  (That's what they used to do in pre-computerized days.)
Forty years ago, they came up with methods to categorize fingerprints,
enter that data into the computer, narrow the field down to only a few
possible hits, and then manually searched those few.  Over the decades,
this technique has been refined to the point where the computer can now
generate the biometric data itself, and narrow it down to either one or
zero hits.

> If anyone has pointers to particularly good articles on how it actually
> works and why it should be deemed reliable in light of a statement like the
> one Ken just put forth, I'm up for a little "light" reading.  I somehow
> doubt that places would be using it if it doesn't work accurately, but so
> far what's been presented here doesn't indicate that it should.
[...]

Some possible resources:

    http://www.fbi.gov  -- search for "biometrics" gives 17 hits.

    http://biometrics.cse.msu.edu/

    http://www.cse.scu.edu/~tschwarz/coen350_03/Lectures/authentication.html

Try Google or BrainBoost for numerous other resources.

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| Kenneth J. Brody        | www.hvcomputer.com |                             |
| kenbrody at spamcop.net | www.fptech.com     | #include <std_disclaimer.h> |
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