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Author
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Topic: Info on Layered Voice Analysis
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Dan S
Member
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posted 08-22-2009 09:56 AM
  
Hot off the press in Journal of Forensic Sciences, a study in which a Layered Voice Analysis system was tested independently and found to be effective at the chance level. In other words, you might as well flip a coin.Here’s the abstract: This study was designed to evaluate commonly used voice stress analyzers—in this case the layered voice analysis (LVA) system. The research protocol involved the use of a speech database containing materials recorded while highly controlled deception and stress levels were systematically varied. Subjects were 24 each males/females (age range 18–63 years) drawn from a diverse population. All held strong views about some issue; they were required to make intense contradictory statements while believing that they would be heard/seen by peers. The LVA system was then evaluated by means of a double blind study using two types of examiners: a pair of scientists trained and certified by the manufacturer in the proper use of the system and two highly experienced LVA instructors provided by this same firm. The results showed that the “true positive” (or hit) rates for all examiners averaged near chance (42–56%) for all conditions, types of materials (e.g., stress vs. unstressed, truth vs. deception), and examiners (scientists vs. manufacturers). Most importantly, the false positive rate was very high, ranging from 40% to 65%. Sensitivity statistics confirmed that the LVA system operated at about chance levels in the detection of truth, deception, and the presence of high and low vocal stress states. Reference: James D. Harnsberger, Harry Hollien, Camilo A. Martin, and Kevin A. Hollien (in press) Stress and Deception in Speech: Evaluating Layered Voice Analysis. Journal of Forensic Sciences
http://deception.crimepsychblog.com/ IP: Logged |
Ted Todd
Member
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posted 08-22-2009 05:06 PM
Dan,This is exactly the kind of info that needs to be posted on the APA, NPA and AAPP web sites. Is that going to happen? Ted IP: Logged |
Dan S
Member
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posted 08-23-2009 07:41 AM
I can only speak for the APA but I will pass this information along to our fellow associations. Hopefully it will be posted on www.voicestress.com IP: Logged |
rcgilford
Member
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posted 08-23-2009 08:11 AM
For those who attended the APA seminar in Nashville, you will find on the CD or flash drive that you received a powerpoint presentation prepared by Dr Horvath on two studies done by the University of Florida and the University of Oklahoma pertaining to voice stress/LVA. IP: Logged |
Barry C
Member
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posted 08-23-2009 11:41 AM
Dan,I don't think that's the right link. Try this one.
www.voicestress.org IP: Logged |
Ted Todd
Member
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posted 08-23-2009 12:43 PM
Barry,Thanks for the link. Who set up and maintains this site? Ted IP: Logged |
rnelson
Member
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posted 08-23-2009 04:05 PM
I think that is Skip Webb who maintains that site.r ------------------
"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)
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skipwebb
Member
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posted 08-25-2009 08:43 AM
I posted both the Florida and the Oklahoma study on the voicestress.org web site months ago. I also put quotes from both on the splash portion of the page.IP: Logged |
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