ARTICLE: Gut feeling key to fingerprint matching

[Steve Everist]

http://www.abc.net.au/science/articles/ ... 176615.htm

Gut feeling key to fingerprint matching

Monday, 23 February 2015 Anna Salleh
ABC

Forensic experts rely on a surprising level of gut instinct to accurately match fingerprints to catch criminals, according to a new study

"Gut feeling is responsible for a lot more of the accuracy than many people think, even the experts themselves," says Dr Matthew Thompson of the University of Queensland School of Psychology.

While TV programs might give the impression that fingerprint matching is carried out by computers, this is actually the job of fingerprint examiners, who may use a shortlist of possible matches generated by a computer.

Interestingly very little is understood about how fingerprint examiners do this job.

Thompson says fingerprint examiners are trained to match by analysing certain features on fingerprints according to a set of rules.

"But our conclusion is that experts are still impressively accurate when they don't have those features available," he says.

In a series of experiments, Thompson and Dr Jason Tangen studied what happened when fingerprint examiners lacked the detail or time needed to analyse fingerprints.

They were asked to match prints that were upside down and were unclear, and in another case, given just a couple of seconds to match prints.

The experts amazed the researchers and themselves with how well they performed under these less than ideal circumstances.

Their findings are published in a recent issue of PLOS ONE http://dx.doi.org/10.1371/journal.pone.0114759.

"The results from these experiments suggest that a surprising amount of fingerprint examiners' accuracy can be accounted for by non-analytic thinking, which is intuitive, unconscious, associative, and effortless," says Thompson.

"You can think of it as a sort of gut feeling."

Peak performance

Preliminary evidence suggests accuracy in fingerprint identification tends to peak after an expert has had a few years' of experience, says Thompson.

While textbooks are still important, Thompson says a good gut feeling appears to come from a lot of exposure to matching and non-matching prints, giving experts the ability to quickly recognise which category a set of prints are in.

He says fingerprint identification involves a similar skill to that used by a radiologist who is able to rapidly tell the difference between a normal or abnormal cancer scan.

"The mark of a real expert is someone who can perform accurately and quickly," says Thompson.

While fingerprint examiners may make analytical explanations to justify their judgment about a set of prints, Thompson says, these may not be the actual basis upon which they have drawn their conclusion.

"If a lot of their decision-making is unconscious and gut feeling, you can't explain the basis of their decisions," says Thompson.

Matthew Thompson won the International Three Minute Thesis Competition for his research on fingerprint analysis. You can see his presentation here.

[Tazman]

For those in the YouTube generation who can't read and have a short attention span, here is the 3 Minute Synopsis on YouTube:
https://www.youtube.com/watch?v=pvjPzsL ... e=youtu.be

For those more serious scientists who would like the full Thesis, it can be found here:
http://journals.plos.org/plosone/articl ... ne.0114759

One more giant step toward science.
Damn, this business was fun in the last millenium. Not so sure anymore.

[Boyd Baumgartner]

[Tazman]

Wow! That explains it!

I have eaten a few burritos that gave me a warm, fuzzy feeling.

Now I know what a REAL individualization is!!!

[NRivera]

I'm no Doctor of Psychology but I'm almost certain that if you forced a gastroenterologist to make a diagnosis in 2 minutes he'd have a gut feeling too.