On Thu, 2 Dec 1999, Bill Bachofner wrote:
<snip>
>
> She was thinking of comparing the bloodhound's ability to ID a
> suspect vs. the human ability by replicating the classroom study
> where a student explodes into the classroom and shouts something at
> the professor and then leaves almost immediately. The class is then
> questioned as to their recall and the accuracy of their recall is
> compared with the actual event and suspect.
>
> At this point the bloodhound would be brought into the classroom and
> would "gather its data" before proceeding to track the suspect down
> somewhere on-campus. The accuracy of the bloodhound's ID would be
> compared with the class'.
>
As described, I doubt that it would work. If the bloodhound was
brought into the classroom after the crime was perpetuated, the dog
would have no way of identifying which of the many smells in the
classroom belonged to the perp. Even if the dog was present during the
commission of the crime, this would undoubtedly be too difficult for
it. How would the poor dumb beast know that shouting at the professor
is a crime? Even students don't know that!
No, a conventional test would require that some odoriferous article
belonging to the perp be presented to the dog. Then it could be asked
to nose him or her out.
If this is done, I'd say that one precaution is absolutely necessary.
This is that the handler not know who the guilty party is. Otherwise
you may only be demonstrating the ubiquitous Clever Hans effect or
that the handler deludes him/herself into believing the dog made the
identification when the handler actually did. (Is there a name for
this misinterpretation? It's the same one that sunk facilitated
communication--the autistic child isn't communicating, it's the
facilitator).
I've often wondered about the scientific accuracy of claims that dogs
can be used to track people, sniff out drugs, etc. They seem based
mostly on anecdotal reports. It might be interesting to review the
literature and see if there was any serious attempt to rule out Clever
Hans and identification by the handler.
-Stephen
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Stephen Black, Ph.D. tel: (819) 822-9600 ext 2470
Department of Psychology fax: (819) 822-9661
Bishop's University e-mail: [EMAIL PROTECTED]
Lennoxville, QC
J1M 1Z7
Canada Department web page at http://www.ubishops.ca/ccc/div/soc/psy
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